marlin/Marlin/Marlin_main.cpp

/**
 * Marlin 3D Printer Firmware
 * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

/**
 * About Marlin
 *
 * This firmware is a mashup between Sprinter and grbl.
 *  - https://github.com/kliment/Sprinter
 *  - https://github.com/simen/grbl/tree
 *
 * It has preliminary support for Matthew Roberts advance algorithm
 *  - http://reprap.org/pipermail/reprap-dev/2011-May/003323.html
 */

#include "Marlin.h"

#if HAS_ABL
  #include "vector_3.h"
#endif

#if ENABLED(AUTO_BED_LEVELING_LINEAR)
  #include "qr_solve.h"
#elif ENABLED(MESH_BED_LEVELING)
  #include "mesh_bed_leveling.h"
#endif

#if ENABLED(BEZIER_CURVE_SUPPORT)
  #include "planner_bezier.h"
#endif

#include "ultralcd.h"
#include "planner.h"
#include "stepper.h"
#include "endstops.h"
#include "temperature.h"
#include "cardreader.h"
#include "configuration_store.h"
#include "language.h"
#include "pins_arduino.h"
#include "math.h"
#include "nozzle.h"
#include "duration_t.h"
#include "types.h"

#if ENABLED(USE_WATCHDOG)
  #include "watchdog.h"
#endif

#if ENABLED(BLINKM)
  #include "blinkm.h"
  #include "Wire.h"
#endif

#if HAS_SERVOS
  #include "servo.h"
#endif

#if HAS_DIGIPOTSS
  #include <SPI.h>
#endif

#if ENABLED(DAC_STEPPER_CURRENT)
  #include "stepper_dac.h"
#endif

#if ENABLED(EXPERIMENTAL_I2CBUS)
  #include "twibus.h"
#endif

/**
 * Look here for descriptions of G-codes:
 *  - http://linuxcnc.org/handbook/gcode/g-code.html
 *  - http://objects.reprap.org/wiki/Mendel_User_Manual:_RepRapGCodes
 *
 * Help us document these G-codes online:
 *  - https://github.com/MarlinFirmware/Marlin/wiki/G-Code-in-Marlin
 *  - http://reprap.org/wiki/G-code
 *
 * -----------------
 * Implemented Codes
 * -----------------
 *
 * "G" Codes
 *
 * G0  -> G1
 * G1  - Coordinated Movement X Y Z E
 * G2  - CW ARC
 * G3  - CCW ARC
 * G4  - Dwell S<seconds> or P<milliseconds>
 * G5  - Cubic B-spline with XYZE destination and IJPQ offsets
 * G10 - Retract filament according to settings of M207
 * G11 - Retract recover filament according to settings of M208
 * G12 - Clean tool
 * G20 - Set input units to inches
 * G21 - Set input units to millimeters
 * G28 - Home one or more axes
 * G29 - Detailed Z probe, probes the bed at 3 or more points.  Will fail if you haven't homed yet.
 * G30 - Single Z probe, probes bed at current XY location.
 * G31 - Dock sled (Z_PROBE_SLED only)
 * G32 - Undock sled (Z_PROBE_SLED only)
 * G38 - Probe target - similar to G28 except it uses the Z_Probe for all three axis
 * G90 - Use Absolute Coordinates
 * G91 - Use Relative Coordinates
 * G92 - Set current position to coordinates given
 *
 * "M" Codes
 *
 * M0   - Unconditional stop - Wait for user to press a button on the LCD (Only if ULTRA_LCD is enabled)
 * M1   - Same as M0
 * M17  - Enable/Power all stepper motors
 * M18  - Disable all stepper motors; same as M84
 * M20  - List SD card. (Requires SDSUPPORT)
 * M21  - Init SD card. (Requires SDSUPPORT)
 * M22  - Release SD card. (Requires SDSUPPORT)
 * M23  - Select SD file: "M23 /path/file.gco". (Requires SDSUPPORT)
 * M24  - Start/resume SD print. (Requires SDSUPPORT)
 * M25  - Pause SD print. (Requires SDSUPPORT)
 * M26  - Set SD position in bytes: "M26 S12345". (Requires SDSUPPORT)
 * M27  - Report SD print status. (Requires SDSUPPORT)
 * M28  - Start SD write: "M28 /path/file.gco". (Requires SDSUPPORT)
 * M29  - Stop SD write. (Requires SDSUPPORT)
 * M30  - Delete file from SD: "M30 /path/file.gco"
 * M31  - Report time since last M109 or SD card start to serial.
 * M32  - Select file and start SD print: "M32 [S<bytepos>] !/path/file.gco#". (Requires SDSUPPORT)
 *        Use P to run other files as sub-programs: "M32 P !filename#"
 *        The '#' is necessary when calling from within sd files, as it stops buffer prereading
 * M33  - Get the longname version of a path. (Requires LONG_FILENAME_HOST_SUPPORT)
 * M42  - Change pin status via gcode: M42 P<pin> S<value>. LED pin assumed if P is omitted.
 * M48  - Measure Z Probe repeatability: M48 P<points> X<pos> Y<pos> V<level> E<engage> L<legs>. (Requires Z_MIN_PROBE_REPEATABILITY_TEST)
 * M75  - Start the print job timer.
 * M76  - Pause the print job timer.
 * M77  - Stop the print job timer.
 * M78  - Show statistical information about the print jobs. (Requires PRINTCOUNTER)
 * M80  - Turn on Power Supply. (Requires POWER_SUPPLY)
 * M81  - Turn off Power Supply. (Requires POWER_SUPPLY)
 * M82  - Set E codes absolute (default).
 * M83  - Set E codes relative while in Absolute (G90) mode.
 * M84  - Disable steppers until next move, or use S<seconds> to specify an idle
 *        duration after which steppers should turn off. S0 disables the timeout.
 * M85  - Set inactivity shutdown timer with parameter S<seconds>. To disable set zero (default)
 * M92  - Set planner.axis_steps_per_mm for one or more axes.
 * M104 - Set extruder target temp.
 * M105 - Report current temperatures.
 * M106 - Fan on.
 * M107 - Fan off.
 * M108 - Break out of heating loops (M109, M190, M303). With no controller, breaks out of M0/M1. (Requires EMERGENCY_PARSER)
 * M109 - Sxxx Wait for extruder current temp to reach target temp. Waits only when heating
 *        Rxxx Wait for extruder current temp to reach target temp. Waits when heating and cooling
 *        IF AUTOTEMP is enabled, S<mintemp> B<maxtemp> F<factor>. Exit autotemp by any M109 without F
 * M110 - Set the current line number. (Used by host printing)
 * M111 - Set debug flags: "M111 S<flagbits>". See flag bits defined in enum.h.
 * M112 - Emergency stop.
 * M113 - Get or set the timeout interval for Host Keepalive "busy" messages. (Requires HOST_KEEPALIVE_FEATURE)
 * M114 - Report current position.
 * M115 - Report capabilities.
 * M117 - Display a message on the controller screen. (Requires an LCD)
 * M119 - Report endstops status.
 * M120 - Enable endstops detection.
 * M121 - Disable endstops detection.
 * M126 - Solenoid Air Valve Open. (Requires BARICUDA)
 * M127 - Solenoid Air Valve Closed. (Requires BARICUDA)
 * M128 - EtoP Open. (Requires BARICUDA)
 * M129 - EtoP Closed. (Requires BARICUDA)
 * M140 - Set bed target temp. S<temp>
 * M145 - Set heatup values for materials on the LCD. H<hotend> B<bed> F<fan speed> for S<material> (0=PLA, 1=ABS)
 * M149 - Set temperature units. (Requires TEMPERATURE_UNITS_SUPPORT)
 * M150 - Set BlinkM Color R<red> U<green> B<blue>. Values 0-255. (Requires BLINKM)
 * M163 - Set a single proportion for a mixing extruder. (Requires MIXING_EXTRUDER)
 * M164 - Save the mix as a virtual extruder. (Requires MIXING_EXTRUDER and MIXING_VIRTUAL_TOOLS)
 * M165 - Set the proportions for a mixing extruder. Use parameters ABCDHI to set the mixing factors. (Requires MIXING_EXTRUDER)
 * M190 - Sxxx Wait for bed current temp to reach target temp. ** Waits only when heating! **
 *        Rxxx Wait for bed current temp to reach target temp. ** Waits for heating or cooling. **
 * M200 - Set filament diameter, D<diameter>, setting E axis units to cubic. (Use S0 to revert to linear units.)
 * M201 - Set max acceleration in units/s^2 for print moves: "M201 X<accel> Y<accel> Z<accel> E<accel>"
 * M202 - Set max acceleration in units/s^2 for travel moves: "M202 X<accel> Y<accel> Z<accel> E<accel>" ** UNUSED IN MARLIN! **
 * M203 - Set maximum feedrate: "M203 X<fr> Y<fr> Z<fr> E<fr>" in units/sec.
 * M204 - Set default acceleration in units/sec^2: P<printing> R<extruder_only> T<travel>
 * M205 - Set advanced settings. Current units apply:
            S<print> T<travel> minimum speeds
            B<minimum segment time>
            X<max xy jerk>, Z<max Z jerk>, E<max E jerk>
 * M206 - Set additional homing offset.
 * M207 - Set Retract Length: S<length>, Feedrate: F<units/min>, and Z lift: Z<distance>. (Requires FWRETRACT)
 * M208 - Set Recover (unretract) Additional (!) Length: S<length> and Feedrate: F<units/min>. (Requires FWRETRACT)
 * M209 - Turn Automatic Retract Detection on/off: S<0|1> (For slicers that don't support G10/11). (Requires FWRETRACT)
          Every normal extrude-only move will be classified as retract depending on the direction.
 * M211 - Enable, Disable, and/or Report software endstops: S<0|1>
 * M218 - Set a tool offset: "M218 T<index> X<offset> Y<offset>". (Requires 2 or more extruders)
 * M220 - Set Feedrate Percentage: "M220 S<percent>" (i.e., "FR" on the LCD)
 * M221 - Set Flow Percentage: "M221 S<percent>"
 * M226 - Wait until a pin is in a given state: "M226 P<pin> S<state>"
 * M240 - Trigger a camera to take a photograph. (Requires CHDK or PHOTOGRAPH_PIN)
 * M250 - Set LCD contrast: "M250 C<contrast>" (0-63). (Requires LCD support)
 * M280 - Set servo position absolute: "M280 P<index> S<angle|µs>". (Requires servos)
 * M300 - Play beep sound S<frequency Hz> P<duration ms>
 * M301 - Set PID parameters P I and D. (Requires PIDTEMP)
 * M302 - Allow cold extrudes, or set the minimum extrude S<temperature>. (Requires PREVENT_COLD_EXTRUSION)
 * M303 - PID relay autotune S<temperature> sets the target temperature. Default 150C. (Requires PIDTEMP)
 * M304 - Set bed PID parameters P I and D. (Requires PIDTEMPBED)
 * M380 - Activate solenoid on active extruder. (Requires EXT_SOLENOID)
 * M381 - Disable all solenoids. (Requires EXT_SOLENOID)
 * M400 - Finish all moves.
 * M401 - Lower Z probe. (Requires a probe)
 * M402 - Raise Z probe. (Requires a probe)
 * M404 - Display or set the Nominal Filament Width: "W<diameter>". (Requires FILAMENT_WIDTH_SENSOR)
 * M405 - Enable Filament Sensor flow control. "M405 D<delay_cm>". (Requires FILAMENT_WIDTH_SENSOR)
 * M406 - Disable Filament Sensor flow control. (Requires FILAMENT_WIDTH_SENSOR)
 * M407 - Display measured filament diameter in millimeters. (Requires FILAMENT_WIDTH_SENSOR)
 * M410 - Quickstop. Abort all planned moves.
 * M420 - Enable/Disable Leveling (with current values) S1=enable S0=disable (Requires MESH_BED_LEVELING or ABL)
 * M421 - Set a single Z coordinate in the Mesh Leveling grid. X<units> Y<units> Z<units> (Requires MESH_BED_LEVELING)
 * M428 - Set the home_offset based on the current_position. Nearest edge applies.
 * M500 - Store parameters in EEPROM. (Requires EEPROM_SETTINGS)
 * M501 - Restore parameters from EEPROM. (Requires EEPROM_SETTINGS)
 * M502 - Revert to the default "factory settings". ** Does not write them to EEPROM! **
 * M503 - Print the current settings (in memory): "M503 S<verbose>". S0 specifies compact output.
 * M540 - Enable/disable SD card abort on endstop hit: "M540 S<state>". (Requires ABORT_ON_ENDSTOP_HIT_FEATURE_ENABLED)
 * M600 - Pause for filament change: "M600 X<pos> Y<pos> Z<raise> E<first_retract> L<later_retract>". (Requires FILAMENT_CHANGE_FEATURE)
 * M665 - Set delta configurations: "M665 L<diagonal rod> R<delta radius> S<segments/s>" (Requires DELTA)
 * M666 - Set delta endstop adjustment. (Requires DELTA)
 * M605 - Set dual x-carriage movement mode: "M605 S<mode> [X<x_offset>] [R<temp_offset>]". (Requires DUAL_X_CARRIAGE)
 * M851 - Set Z probe's Z offset in current units. (Negative = below the nozzle.)
 * M907 - Set digital trimpot motor current using axis codes. (Requires a board with digital trimpots)
 * M908 - Control digital trimpot directly. (Requires DAC_STEPPER_CURRENT or DIGIPOTSS_PIN)
 * M909 - Print digipot/DAC current value. (Requires DAC_STEPPER_CURRENT)
 * M910 - Commit digipot/DAC value to external EEPROM via I2C. (Requires DAC_STEPPER_CURRENT)
 * M350 - Set microstepping mode. (Requires digital microstepping pins.)
 * M351 - Toggle MS1 MS2 pins directly. (Requires digital microstepping pins.)
 *
 * ************ SCARA Specific - This can change to suit future G-code regulations
 * M360 - SCARA calibration: Move to cal-position ThetaA (0 deg calibration)
 * M361 - SCARA calibration: Move to cal-position ThetaB (90 deg calibration - steps per degree)
 * M362 - SCARA calibration: Move to cal-position PsiA (0 deg calibration)
 * M363 - SCARA calibration: Move to cal-position PsiB (90 deg calibration - steps per degree)
 * M364 - SCARA calibration: Move to cal-position PSIC (90 deg to Theta calibration position)
 * ************* SCARA End ***************
 *
 * ************ Custom codes - This can change to suit future G-code regulations
 * M100 - Watch Free Memory (For Debugging). (Requires M100_FREE_MEMORY_WATCHER)
 * M928 - Start SD logging: "M928 filename.gco". Stop with M29. (Requires SDSUPPORT)
 * M999 - Restart after being stopped by error
 *
 * "T" Codes
 *
 * T0-T3 - Select an extruder (tool) by index: "T<n> F<units/min>"
 *
 */

#if ENABLED(M100_FREE_MEMORY_WATCHER)
  void gcode_M100();
#endif

#if ENABLED(SDSUPPORT)
  CardReader card;
#endif

#if ENABLED(EXPERIMENTAL_I2CBUS)
  TWIBus i2c;
#endif

#ifdef G38_2_3
bool G38_flag = false;   // init G38 flags
bool G38_flag_pass = false;
#endif

bool Running = true;

uint8_t marlin_debug_flags = DEBUG_NONE;

float current_position[NUM_AXIS] = { 0.0 };
static float destination[NUM_AXIS] = { 0.0 };
bool axis_known_position[XYZ] = { false };
bool axis_homed[XYZ] = { false };

static long gcode_N, gcode_LastN, Stopped_gcode_LastN = 0;

static char command_queue[BUFSIZE][MAX_CMD_SIZE];
static char* current_command, *current_command_args;
static uint8_t cmd_queue_index_r = 0,
               cmd_queue_index_w = 0,
               commands_in_queue = 0;

#if ENABLED(INCH_MODE_SUPPORT)
  float linear_unit_factor = 1.0;
  float volumetric_unit_factor = 1.0;
#endif
#if ENABLED(TEMPERATURE_UNITS_SUPPORT)
  TempUnit input_temp_units = TEMPUNIT_C;
#endif

/**
 * Feed rates are often configured with mm/m
 * but the planner and stepper like mm/s units.
 */
float constexpr homing_feedrate_mm_s[] = {
  #if ENABLED(DELTA)
    MMM_TO_MMS(HOMING_FEEDRATE_Z), MMM_TO_MMS(HOMING_FEEDRATE_Z),
  #else
    MMM_TO_MMS(HOMING_FEEDRATE_XY), MMM_TO_MMS(HOMING_FEEDRATE_XY),
  #endif
  MMM_TO_MMS(HOMING_FEEDRATE_Z), 0
};
static float feedrate_mm_s = MMM_TO_MMS(1500.0), saved_feedrate_mm_s;
int feedrate_percentage = 100, saved_feedrate_percentage;

bool axis_relative_modes[] = AXIS_RELATIVE_MODES;
int flow_percentage[EXTRUDERS] = ARRAY_BY_EXTRUDERS1(100);
bool volumetric_enabled = false;
float filament_size[EXTRUDERS] = ARRAY_BY_EXTRUDERS1(DEFAULT_NOMINAL_FILAMENT_DIA);
float volumetric_multiplier[EXTRUDERS] = ARRAY_BY_EXTRUDERS1(1.0);

// The distance that XYZ has been offset by G92. Reset by G28.
float position_shift[XYZ] = { 0 };

// This offset is added to the configured home position.
// Set by M206, M428, or menu item. Saved to EEPROM.
float home_offset[XYZ] = { 0 };

// Software Endstops are based on the configured limits.
#if ENABLED(min_software_endstops) || ENABLED(max_software_endstops)
  bool soft_endstops_enabled = true;
#endif
float soft_endstop_min[XYZ] = { X_MIN_POS, Y_MIN_POS, Z_MIN_POS },
      soft_endstop_max[XYZ] = { X_MAX_POS, Y_MAX_POS, Z_MAX_POS };

#if FAN_COUNT > 0
  int fanSpeeds[FAN_COUNT] = { 0 };
#endif

// The active extruder (tool). Set with T<extruder> command.
uint8_t active_extruder = 0;

// Relative Mode. Enable with G91, disable with G90.
static bool relative_mode = false;

volatile bool wait_for_heatup = true;

#if ENABLED(EMERGENCY_PARSER) && DISABLED(ULTIPANEL)
  volatile bool wait_for_user = false;
#endif

const char errormagic[] PROGMEM = "Error:";
const char echomagic[] PROGMEM = "echo:";
const char axis_codes[NUM_AXIS] = {'X', 'Y', 'Z', 'E'};

static int serial_count = 0;

// GCode parameter pointer used by code_seen(), code_value_float(), etc.
static char* seen_pointer;

// Next Immediate GCode Command pointer. NULL if none.
const char* queued_commands_P = NULL;

const int sensitive_pins[] = SENSITIVE_PINS; ///< Sensitive pin list for M42

// Inactivity shutdown
millis_t previous_cmd_ms = 0;
static millis_t max_inactive_time = 0;
static millis_t stepper_inactive_time = (DEFAULT_STEPPER_DEACTIVE_TIME) * 1000UL;

// Print Job Timer
#if ENABLED(PRINTCOUNTER)
  PrintCounter print_job_timer = PrintCounter();
#else
  Stopwatch print_job_timer = Stopwatch();
#endif

// Buzzer - I2C on the LCD or a BEEPER_PIN
#if ENABLED(LCD_USE_I2C_BUZZER)
  #define BUZZ(d,f) lcd_buzz(d, f)
#elif HAS_BUZZER
  Buzzer buzzer;
  #define BUZZ(d,f) buzzer.tone(d, f)
#else
  #define BUZZ(d,f) NOOP
#endif

static uint8_t target_extruder;

#if HAS_BED_PROBE
  float zprobe_zoffset = Z_PROBE_OFFSET_FROM_EXTRUDER;
#endif

#define PLANNER_XY_FEEDRATE() (min(planner.max_feedrate_mm_s[X_AXIS], planner.max_feedrate_mm_s[Y_AXIS]))

#if HAS_ABL
  float xy_probe_feedrate_mm_s = MMM_TO_MMS(XY_PROBE_SPEED);
  #define XY_PROBE_FEEDRATE_MM_S xy_probe_feedrate_mm_s
#elif defined(XY_PROBE_SPEED)
  #define XY_PROBE_FEEDRATE_MM_S MMM_TO_MMS(XY_PROBE_SPEED)
#else
  #define XY_PROBE_FEEDRATE_MM_S PLANNER_XY_FEEDRATE()
#endif

#if ENABLED(Z_DUAL_ENDSTOPS)
  float z_endstop_adj = 0;
#endif

// Extruder offsets
#if HOTENDS > 1
  float hotend_offset[][HOTENDS] = {
    HOTEND_OFFSET_X,
    HOTEND_OFFSET_Y
    #ifdef HOTEND_OFFSET_Z
      , HOTEND_OFFSET_Z
    #endif
  };
#endif

#if HAS_Z_SERVO_ENDSTOP
  const int z_servo_angle[2] = Z_SERVO_ANGLES;
#endif

#if ENABLED(BARICUDA)
  int baricuda_valve_pressure = 0;
  int baricuda_e_to_p_pressure = 0;
#endif

#if ENABLED(FWRETRACT)

  bool autoretract_enabled = false;
  bool retracted[EXTRUDERS] = { false };
  bool retracted_swap[EXTRUDERS] = { false };

  float retract_length = RETRACT_LENGTH;
  float retract_length_swap = RETRACT_LENGTH_SWAP;
  float retract_feedrate_mm_s = RETRACT_FEEDRATE;
  float retract_zlift = RETRACT_ZLIFT;
  float retract_recover_length = RETRACT_RECOVER_LENGTH;
  float retract_recover_length_swap = RETRACT_RECOVER_LENGTH_SWAP;
  float retract_recover_feedrate_mm_s = RETRACT_RECOVER_FEEDRATE;

#endif // FWRETRACT

#if ENABLED(ULTIPANEL) && HAS_POWER_SWITCH
  bool powersupply =
    #if ENABLED(PS_DEFAULT_OFF)
      false
    #else
      true
    #endif
  ;
#endif

#if ENABLED(DELTA)

  #define SIN_60 0.8660254037844386
  #define COS_60 0.5

  float delta[ABC],
        endstop_adj[ABC] = { 0 };

  // these are the default values, can be overriden with M665
  float delta_radius = DELTA_RADIUS,
        delta_tower1_x = -SIN_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1), // front left tower
        delta_tower1_y = -COS_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_1),
        delta_tower2_x =  SIN_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2), // front right tower
        delta_tower2_y = -COS_60 * (delta_radius + DELTA_RADIUS_TRIM_TOWER_2),
        delta_tower3_x = 0,                                                    // back middle tower
        delta_tower3_y = (delta_radius + DELTA_RADIUS_TRIM_TOWER_3),
        delta_diagonal_rod = DELTA_DIAGONAL_ROD,
        delta_diagonal_rod_trim_tower_1 = DELTA_DIAGONAL_ROD_TRIM_TOWER_1,
        delta_diagonal_rod_trim_tower_2 = DELTA_DIAGONAL_ROD_TRIM_TOWER_2,
        delta_diagonal_rod_trim_tower_3 = DELTA_DIAGONAL_ROD_TRIM_TOWER_3,
        delta_diagonal_rod_2_tower_1 = sq(delta_diagonal_rod + delta_diagonal_rod_trim_tower_1),
        delta_diagonal_rod_2_tower_2 = sq(delta_diagonal_rod + delta_diagonal_rod_trim_tower_2),
        delta_diagonal_rod_2_tower_3 = sq(delta_diagonal_rod + delta_diagonal_rod_trim_tower_3),
        delta_segments_per_second = DELTA_SEGMENTS_PER_SECOND,
        delta_clip_start_height = Z_MAX_POS;

  float delta_safe_distance_from_top();

#else

  static bool home_all_axis = true;

#endif

#if ENABLED(AUTO_BED_LEVELING_BILINEAR)
  int bilinear_grid_spacing[2] = { 0 }, bilinear_start[2] = { 0 };
  float bed_level_grid[ABL_GRID_POINTS_X][ABL_GRID_POINTS_Y];
#endif

#if IS_SCARA
  // Float constants for SCARA calculations
  const float L1 = SCARA_LINKAGE_1, L2 = SCARA_LINKAGE_2,
              L1_2 = sq(float(L1)), L1_2_2 = 2.0 * L1_2,
              L2_2 = sq(float(L2));

  float delta_segments_per_second = SCARA_SEGMENTS_PER_SECOND,
        delta[ABC];
#endif

float cartes[XYZ] = { 0 };

#if ENABLED(FILAMENT_WIDTH_SENSOR)
  bool filament_sensor = false;  //M405 turns on filament_sensor control, M406 turns it off
  float filament_width_nominal = DEFAULT_NOMINAL_FILAMENT_DIA,  // Nominal filament width. Change with M404
        filament_width_meas = DEFAULT_MEASURED_FILAMENT_DIA;    // Measured filament diameter
  int8_t measurement_delay[MAX_MEASUREMENT_DELAY + 1]; // Ring buffer to delayed measurement. Store extruder factor after subtracting 100
  int filwidth_delay_index[2] = { 0, -1 };  // Indexes into ring buffer
  int meas_delay_cm = MEASUREMENT_DELAY_CM;  //distance delay setting
#endif

#if ENABLED(FILAMENT_RUNOUT_SENSOR)
  static bool filament_ran_out = false;
#endif

#if ENABLED(FILAMENT_CHANGE_FEATURE)
  FilamentChangeMenuResponse filament_change_menu_response;
#endif

#if ENABLED(MIXING_EXTRUDER)
  float mixing_factor[MIXING_STEPPERS];
  #if MIXING_VIRTUAL_TOOLS > 1
    float mixing_virtual_tool_mix[MIXING_VIRTUAL_TOOLS][MIXING_STEPPERS];
  #endif
#endif

static bool send_ok[BUFSIZE];

#if HAS_SERVOS
  Servo servo[NUM_SERVOS];
  #define MOVE_SERVO(I, P) servo[I].move(P)
  #if HAS_Z_SERVO_ENDSTOP
    #define DEPLOY_Z_SERVO() MOVE_SERVO(Z_ENDSTOP_SERVO_NR, z_servo_angle[0])
    #define STOW_Z_SERVO() MOVE_SERVO(Z_ENDSTOP_SERVO_NR, z_servo_angle[1])
  #endif
#endif

#ifdef CHDK
  millis_t chdkHigh = 0;
  boolean chdkActive = false;
#endif

#if ENABLED(PID_EXTRUSION_SCALING)
  int lpq_len = 20;
#endif

#if ENABLED(HOST_KEEPALIVE_FEATURE)
  static MarlinBusyState busy_state = NOT_BUSY;
  static millis_t next_busy_signal_ms = 0;
  uint8_t host_keepalive_interval = DEFAULT_KEEPALIVE_INTERVAL;
  #define KEEPALIVE_STATE(n) do{ busy_state = n; }while(0)
#else
  #define host_keepalive() ;
  #define KEEPALIVE_STATE(n) ;
#endif // HOST_KEEPALIVE_FEATURE

#define DEFINE_PGM_READ_ANY(type, reader)       \
  static inline type pgm_read_any(const type *p)  \
  { return pgm_read_##reader##_near(p); }

DEFINE_PGM_READ_ANY(float,       float);
DEFINE_PGM_READ_ANY(signed char, byte);

#define XYZ_CONSTS_FROM_CONFIG(type, array, CONFIG) \
  static const PROGMEM type array##_P[XYZ] =        \
      { X_##CONFIG, Y_##CONFIG, Z_##CONFIG };     \
  static inline type array(int axis)          \
  { return pgm_read_any(&array##_P[axis]); }

XYZ_CONSTS_FROM_CONFIG(float, base_min_pos,   MIN_POS);
XYZ_CONSTS_FROM_CONFIG(float, base_max_pos,   MAX_POS);
XYZ_CONSTS_FROM_CONFIG(float, base_home_pos,  HOME_POS);
XYZ_CONSTS_FROM_CONFIG(float, max_length,     MAX_LENGTH);
XYZ_CONSTS_FROM_CONFIG(float, home_bump_mm,   HOME_BUMP_MM);
XYZ_CONSTS_FROM_CONFIG(signed char, home_dir, HOME_DIR);

/**
 * ***************************************************************************
 * ******************************** FUNCTIONS ********************************
 * ***************************************************************************
 */

void stop();

void get_available_commands();
void process_next_command();
void prepare_move_to_destination();

void get_cartesian_from_steppers();
void set_current_from_steppers_for_axis(const AxisEnum axis);

#if ENABLED(ARC_SUPPORT)
  void plan_arc(float target[NUM_AXIS], float* offset, uint8_t clockwise);
#endif

#if ENABLED(BEZIER_CURVE_SUPPORT)
  void plan_cubic_move(const float offset[4]);
#endif

void serial_echopair_P(const char* s_P, const char *v)   { serialprintPGM(s_P); SERIAL_ECHO(v); }
void serial_echopair_P(const char* s_P, char v)          { serialprintPGM(s_P); SERIAL_CHAR(v); }
void serial_echopair_P(const char* s_P, int v)           { serialprintPGM(s_P); SERIAL_ECHO(v); }
void serial_echopair_P(const char* s_P, long v)          { serialprintPGM(s_P); SERIAL_ECHO(v); }
void serial_echopair_P(const char* s_P, float v)         { serialprintPGM(s_P); SERIAL_ECHO(v); }
void serial_echopair_P(const char* s_P, double v)        { serialprintPGM(s_P); SERIAL_ECHO(v); }
void serial_echopair_P(const char* s_P, unsigned long v) { serialprintPGM(s_P); SERIAL_ECHO(v); }

void tool_change(const uint8_t tmp_extruder, const float fr_mm_s=0.0, bool no_move=false);
static void report_current_position();

#if ENABLED(DEBUG_LEVELING_FEATURE)
  void print_xyz(const char* prefix, const char* suffix, const float x, const float y, const float z) {
    serialprintPGM(prefix);
    SERIAL_ECHOPAIR("(", x);
    SERIAL_ECHOPAIR(", ", y);
    SERIAL_ECHOPAIR(", ", z);
    SERIAL_ECHOPGM(")");

    if (suffix) serialprintPGM(suffix);
    else SERIAL_EOL;
  }

  void print_xyz(const char* prefix, const char* suffix, const float xyz[]) {
    print_xyz(prefix, suffix, xyz[X_AXIS], xyz[Y_AXIS], xyz[Z_AXIS]);
  }

  #if HAS_ABL
    void print_xyz(const char* prefix, const char* suffix, const vector_3 &xyz) {
      print_xyz(prefix, suffix, xyz.x, xyz.y, xyz.z);
    }
  #endif

  #define DEBUG_POS(SUFFIX,VAR) do { \
    print_xyz(PSTR(STRINGIFY(VAR) "="), PSTR(" : " SUFFIX "\n"), VAR); } while(0)
#endif

/**
 * sync_plan_position
 *
 * Set the planner/stepper positions directly from current_position with
 * no kinematic translation. Used for homing axes and cartesian/core syncing.
 */
inline void sync_plan_position() {
  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) DEBUG_POS("sync_plan_position", current_position);
  #endif
  planner.set_position_mm(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS]);
}
inline void sync_plan_position_e() { planner.set_e_position_mm(current_position[E_AXIS]); }

#if IS_KINEMATIC

  inline void sync_plan_position_kinematic() {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("sync_plan_position_kinematic", current_position);
    #endif
    inverse_kinematics(current_position);
    planner.set_position_mm(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], current_position[E_AXIS]);
  }
  #define SYNC_PLAN_POSITION_KINEMATIC() sync_plan_position_kinematic()

#else

  #define SYNC_PLAN_POSITION_KINEMATIC() sync_plan_position()

#endif

#if ENABLED(SDSUPPORT)
  #include "SdFatUtil.h"
  int freeMemory() { return SdFatUtil::FreeRam(); }
#else
extern "C" {
  extern unsigned int __bss_end;
  extern unsigned int __heap_start;
  extern void* __brkval;

  int freeMemory() {
    int free_memory;
    if ((int)__brkval == 0)
      free_memory = ((int)&free_memory) - ((int)&__bss_end);
    else
      free_memory = ((int)&free_memory) - ((int)__brkval);
    return free_memory;
  }
}
#endif //!SDSUPPORT

#if ENABLED(DIGIPOT_I2C)
  extern void digipot_i2c_set_current(int channel, float current);
  extern void digipot_i2c_init();
#endif

/**
 * Inject the next "immediate" command, when possible.
 * Return true if any immediate commands remain to inject.
 */
static bool drain_queued_commands_P() {
  if (queued_commands_P != NULL) {
    size_t i = 0;
    char c, cmd[30];
    strncpy_P(cmd, queued_commands_P, sizeof(cmd) - 1);
    cmd[sizeof(cmd) - 1] = '\0';
    while ((c = cmd[i]) && c != '\n') i++; // find the end of this gcode command
    cmd[i] = '\0';
    if (enqueue_and_echo_command(cmd)) {   // success?
      if (c)                               // newline char?
        queued_commands_P += i + 1;        // advance to the next command
      else
        queued_commands_P = NULL;          // nul char? no more commands
    }
  }
  return (queued_commands_P != NULL);      // return whether any more remain
}

/**
 * Record one or many commands to run from program memory.
 * Aborts the current queue, if any.
 * Note: drain_queued_commands_P() must be called repeatedly to drain the commands afterwards
 */
void enqueue_and_echo_commands_P(const char* pgcode) {
  queued_commands_P = pgcode;
  drain_queued_commands_P(); // first command executed asap (when possible)
}

void clear_command_queue() {
  cmd_queue_index_r = cmd_queue_index_w;
  commands_in_queue = 0;
}

/**
 * Once a new command is in the ring buffer, call this to commit it
 */
inline void _commit_command(bool say_ok) {
  send_ok[cmd_queue_index_w] = say_ok;
  cmd_queue_index_w = (cmd_queue_index_w + 1) % BUFSIZE;
  commands_in_queue++;
}

/**
 * Copy a command directly into the main command buffer, from RAM.
 * Returns true if successfully adds the command
 */
inline bool _enqueuecommand(const char* cmd, bool say_ok=false) {
  if (*cmd == ';' || commands_in_queue >= BUFSIZE) return false;
  strcpy(command_queue[cmd_queue_index_w], cmd);
  _commit_command(say_ok);
  return true;
}

void enqueue_and_echo_command_now(const char* cmd) {
  while (!enqueue_and_echo_command(cmd)) idle();
}

/**
 * Enqueue with Serial Echo
 */
bool enqueue_and_echo_command(const char* cmd, bool say_ok/*=false*/) {
  if (_enqueuecommand(cmd, say_ok)) {
    SERIAL_ECHO_START;
    SERIAL_ECHOPAIR(MSG_Enqueueing, cmd);
    SERIAL_ECHOLNPGM("\"");
    return true;
  }
  return false;
}

void setup_killpin() {
  #if HAS_KILL
    SET_INPUT(KILL_PIN);
    WRITE(KILL_PIN, HIGH);
  #endif
}

#if ENABLED(FILAMENT_RUNOUT_SENSOR)

  void setup_filrunoutpin() {
    SET_INPUT(FIL_RUNOUT_PIN);
    #if ENABLED(ENDSTOPPULLUP_FIL_RUNOUT)
      WRITE(FIL_RUNOUT_PIN, HIGH);
    #endif
  }

#endif

// Set home pin
void setup_homepin(void) {
  #if HAS_HOME
    SET_INPUT(HOME_PIN);
    WRITE(HOME_PIN, HIGH);
  #endif
}

void setup_photpin() {
  #if HAS_PHOTOGRAPH
    OUT_WRITE(PHOTOGRAPH_PIN, LOW);
  #endif
}

void setup_powerhold() {
  #if HAS_SUICIDE
    OUT_WRITE(SUICIDE_PIN, HIGH);
  #endif
  #if HAS_POWER_SWITCH
    #if ENABLED(PS_DEFAULT_OFF)
      OUT_WRITE(PS_ON_PIN, PS_ON_ASLEEP);
    #else
      OUT_WRITE(PS_ON_PIN, PS_ON_AWAKE);
    #endif
  #endif
}

void suicide() {
  #if HAS_SUICIDE
    OUT_WRITE(SUICIDE_PIN, LOW);
  #endif
}

void servo_init() {
  #if NUM_SERVOS >= 1 && HAS_SERVO_0
    servo[0].attach(SERVO0_PIN);
    servo[0].detach(); // Just set up the pin. We don't have a position yet. Don't move to a random position.
  #endif
  #if NUM_SERVOS >= 2 && HAS_SERVO_1
    servo[1].attach(SERVO1_PIN);
    servo[1].detach();
  #endif
  #if NUM_SERVOS >= 3 && HAS_SERVO_2
    servo[2].attach(SERVO2_PIN);
    servo[2].detach();
  #endif
  #if NUM_SERVOS >= 4 && HAS_SERVO_3
    servo[3].attach(SERVO3_PIN);
    servo[3].detach();
  #endif

  #if HAS_Z_SERVO_ENDSTOP
    /**
     * Set position of Z Servo Endstop
     *
     * The servo might be deployed and positioned too low to stow
     * when starting up the machine or rebooting the board.
     * There's no way to know where the nozzle is positioned until
     * homing has been done - no homing with z-probe without init!
     *
     */
    STOW_Z_SERVO();
  #endif
}

/**
 * Stepper Reset (RigidBoard, et.al.)
 */
#if HAS_STEPPER_RESET
  void disableStepperDrivers() {
    OUT_WRITE(STEPPER_RESET_PIN, LOW);  // drive it down to hold in reset motor driver chips
  }
  void enableStepperDrivers() { SET_INPUT(STEPPER_RESET_PIN); }  // set to input, which allows it to be pulled high by pullups
#endif

#if ENABLED(EXPERIMENTAL_I2CBUS) && I2C_SLAVE_ADDRESS > 0

  void i2c_on_receive(int bytes) { // just echo all bytes received to serial
    i2c.receive(bytes);
  }

  void i2c_on_request() {          // just send dummy data for now
    i2c.reply("Hello World!\n");
  }

#endif

void gcode_line_error(const char* err, bool doFlush = true) {
  SERIAL_ERROR_START;
  serialprintPGM(err);
  SERIAL_ERRORLN(gcode_LastN);
  //Serial.println(gcode_N);
  if (doFlush) FlushSerialRequestResend();
  serial_count = 0;
}

inline void get_serial_commands() {
  static char serial_line_buffer[MAX_CMD_SIZE];
  static boolean serial_comment_mode = false;

  // If the command buffer is empty for too long,
  // send "wait" to indicate Marlin is still waiting.
  #if defined(NO_TIMEOUTS) && NO_TIMEOUTS > 0
    static millis_t last_command_time = 0;
    millis_t ms = millis();
    if (commands_in_queue == 0 && !MYSERIAL.available() && ELAPSED(ms, last_command_time + NO_TIMEOUTS)) {
      SERIAL_ECHOLNPGM(MSG_WAIT);
      last_command_time = ms;
    }
  #endif

  /**
   * Loop while serial characters are incoming and the queue is not full
   */
  while (commands_in_queue < BUFSIZE && MYSERIAL.available() > 0) {

    char serial_char = MYSERIAL.read();

    /**
     * If the character ends the line
     */
    if (serial_char == '\n' || serial_char == '\r') {

      serial_comment_mode = false; // end of line == end of comment

      if (!serial_count) continue; // skip empty lines

      serial_line_buffer[serial_count] = 0; // terminate string
      serial_count = 0; //reset buffer

      char* command = serial_line_buffer;

      while (*command == ' ') command++; // skip any leading spaces
      char* npos = (*command == 'N') ? command : NULL; // Require the N parameter to start the line
      char* apos = strchr(command, '*');

      if (npos) {

        boolean M110 = strstr_P(command, PSTR("M110")) != NULL;

        if (M110) {
          char* n2pos = strchr(command + 4, 'N');
          if (n2pos) npos = n2pos;
        }

        gcode_N = strtol(npos + 1, NULL, 10);

        if (gcode_N != gcode_LastN + 1 && !M110) {
          gcode_line_error(PSTR(MSG_ERR_LINE_NO));
          return;
        }

        if (apos) {
          byte checksum = 0, count = 0;
          while (command[count] != '*') checksum ^= command[count++];

          if (strtol(apos + 1, NULL, 10) != checksum) {
            gcode_line_error(PSTR(MSG_ERR_CHECKSUM_MISMATCH));
            return;
          }
          // if no errors, continue parsing
        }
        else {
          gcode_line_error(PSTR(MSG_ERR_NO_CHECKSUM));
          return;
        }

        gcode_LastN = gcode_N;
        // if no errors, continue parsing
      }
      else if (apos) { // No '*' without 'N'
        gcode_line_error(PSTR(MSG_ERR_NO_LINENUMBER_WITH_CHECKSUM), false);
        return;
      }

      // Movement commands alert when stopped
      if (IsStopped()) {
        char* gpos = strchr(command, 'G');
        if (gpos) {
          int codenum = strtol(gpos + 1, NULL, 10);
          switch (codenum) {
            case 0:
            case 1:
            case 2:
            case 3:
              SERIAL_ERRORLNPGM(MSG_ERR_STOPPED);
              LCD_MESSAGEPGM(MSG_STOPPED);
              break;
          }
        }
      }

      #if DISABLED(EMERGENCY_PARSER)
        // If command was e-stop process now
        if (strcmp(command, "M108") == 0) wait_for_heatup = false;
        if (strcmp(command, "M112") == 0) kill(PSTR(MSG_KILLED));
        if (strcmp(command, "M410") == 0) { quickstop_stepper(); }
      #endif

      #if defined(NO_TIMEOUTS) && NO_TIMEOUTS > 0
        last_command_time = ms;
      #endif

      // Add the command to the queue
      _enqueuecommand(serial_line_buffer, true);
    }
    else if (serial_count >= MAX_CMD_SIZE - 1) {
      // Keep fetching, but ignore normal characters beyond the max length
      // The command will be injected when EOL is reached
    }
    else if (serial_char == '\\') {  // Handle escapes
      if (MYSERIAL.available() > 0) {
        // if we have one more character, copy it over
        serial_char = MYSERIAL.read();
        if (!serial_comment_mode) serial_line_buffer[serial_count++] = serial_char;
      }
      // otherwise do nothing
    }
    else { // it's not a newline, carriage return or escape char
      if (serial_char == ';') serial_comment_mode = true;
      if (!serial_comment_mode) serial_line_buffer[serial_count++] = serial_char;
    }

  } // queue has space, serial has data
}

#if ENABLED(SDSUPPORT)

  inline void get_sdcard_commands() {
    static bool stop_buffering = false,
                sd_comment_mode = false;

    if (!card.sdprinting) return;

    /**
     * '#' stops reading from SD to the buffer prematurely, so procedural
     * macro calls are possible. If it occurs, stop_buffering is triggered
     * and the buffer is run dry; this character _can_ occur in serial com
     * due to checksums, however, no checksums are used in SD printing.
     */

    if (commands_in_queue == 0) stop_buffering = false;

    uint16_t sd_count = 0;
    bool card_eof = card.eof();
    while (commands_in_queue < BUFSIZE && !card_eof && !stop_buffering) {
      int16_t n = card.get();
      char sd_char = (char)n;
      card_eof = card.eof();
      if (card_eof || n == -1
          || sd_char == '\n' || sd_char == '\r'
          || ((sd_char == '#' || sd_char == ':') && !sd_comment_mode)
      ) {
        if (card_eof) {
          SERIAL_PROTOCOLLNPGM(MSG_FILE_PRINTED);
          card.printingHasFinished();
          card.checkautostart(true);
        }
        else if (n == -1) {
          SERIAL_ERROR_START;
          SERIAL_ECHOLNPGM(MSG_SD_ERR_READ);
        }
        if (sd_char == '#') stop_buffering = true;

        sd_comment_mode = false; //for new command

        if (!sd_count) continue; //skip empty lines

        command_queue[cmd_queue_index_w][sd_count] = '\0'; //terminate string
        sd_count = 0; //clear buffer

        _commit_command(false);
      }
      else if (sd_count >= MAX_CMD_SIZE - 1) {
        /**
         * Keep fetching, but ignore normal characters beyond the max length
         * The command will be injected when EOL is reached
         */
      }
      else {
        if (sd_char == ';') sd_comment_mode = true;
        if (!sd_comment_mode) command_queue[cmd_queue_index_w][sd_count++] = sd_char;
      }
    }
  }

#endif // SDSUPPORT

/**
 * Add to the circular command queue the next command from:
 *  - The command-injection queue (queued_commands_P)
 *  - The active serial input (usually USB)
 *  - The SD card file being actively printed
 */
void get_available_commands() {

  // if any immediate commands remain, don't get other commands yet
  if (drain_queued_commands_P()) return;

  get_serial_commands();

  #if ENABLED(SDSUPPORT)
    get_sdcard_commands();
  #endif
}

inline bool code_has_value() {
  int i = 1;
  char c = seen_pointer[i];
  while (c == ' ') c = seen_pointer[++i];
  if (c == '-' || c == '+') c = seen_pointer[++i];
  if (c == '.') c = seen_pointer[++i];
  return NUMERIC(c);
}

inline float code_value_float() {
  float ret;
  char* e = strchr(seen_pointer, 'E');
  if (e) {
    *e = 0;
    ret = strtod(seen_pointer + 1, NULL);
    *e = 'E';
  }
  else
    ret = strtod(seen_pointer + 1, NULL);
  return ret;
}

inline unsigned long code_value_ulong() { return strtoul(seen_pointer + 1, NULL, 10); }

inline long code_value_long() { return strtol(seen_pointer + 1, NULL, 10); }

inline int code_value_int() { return (int)strtol(seen_pointer + 1, NULL, 10); }

inline uint16_t code_value_ushort() { return (uint16_t)strtoul(seen_pointer + 1, NULL, 10); }

inline uint8_t code_value_byte() { return (uint8_t)(constrain(strtol(seen_pointer + 1, NULL, 10), 0, 255)); }

inline bool code_value_bool() { return !code_has_value() || code_value_byte() > 0; }

#if ENABLED(INCH_MODE_SUPPORT)
  inline void set_input_linear_units(LinearUnit units) {
    switch (units) {
      case LINEARUNIT_INCH:
        linear_unit_factor = 25.4;
        break;
      case LINEARUNIT_MM:
      default:
        linear_unit_factor = 1.0;
        break;
    }
    volumetric_unit_factor = pow(linear_unit_factor, 3.0);
  }

  inline float axis_unit_factor(int axis) {
    return (axis == E_AXIS && volumetric_enabled ? volumetric_unit_factor : linear_unit_factor);
  }

  inline float code_value_linear_units() { return code_value_float() * linear_unit_factor; }
  inline float code_value_axis_units(int axis) { return code_value_float() * axis_unit_factor(axis); }
  inline float code_value_per_axis_unit(int axis) { return code_value_float() / axis_unit_factor(axis); }

#else

  inline float code_value_linear_units() { return code_value_float(); }
  inline float code_value_axis_units(int axis) { UNUSED(axis); return code_value_float(); }
  inline float code_value_per_axis_unit(int axis) { UNUSED(axis); return code_value_float(); }

#endif

#if ENABLED(TEMPERATURE_UNITS_SUPPORT)
  inline void set_input_temp_units(TempUnit units) { input_temp_units = units; }

  float code_value_temp_abs() {
    switch (input_temp_units) {
      case TEMPUNIT_C:
        return code_value_float();
      case TEMPUNIT_F:
        return (code_value_float() - 32) * 0.5555555556;
      case TEMPUNIT_K:
        return code_value_float() - 272.15;
      default:
        return code_value_float();
    }
  }

  float code_value_temp_diff() {
    switch (input_temp_units) {
      case TEMPUNIT_C:
      case TEMPUNIT_K:
        return code_value_float();
      case TEMPUNIT_F:
        return code_value_float() * 0.5555555556;
      default:
        return code_value_float();
    }
  }
#else
  float code_value_temp_abs() { return code_value_float(); }
  float code_value_temp_diff() { return code_value_float(); }
#endif

FORCE_INLINE millis_t code_value_millis() { return code_value_ulong(); }
inline millis_t code_value_millis_from_seconds() { return code_value_float() * 1000; }

bool code_seen(char code) {
  seen_pointer = strchr(current_command_args, code);
  return (seen_pointer != NULL); // Return TRUE if the code-letter was found
}

/**
 * Set target_extruder from the T parameter or the active_extruder
 *
 * Returns TRUE if the target is invalid
 */
bool get_target_extruder_from_command(int code) {
  if (code_seen('T')) {
    if (code_value_byte() >= EXTRUDERS) {
      SERIAL_ECHO_START;
      SERIAL_CHAR('M');
      SERIAL_ECHO(code);
      SERIAL_ECHOLNPAIR(" " MSG_INVALID_EXTRUDER " ", code_value_byte());
      return true;
    }
    target_extruder = code_value_byte();
  }
  else
    target_extruder = active_extruder;

  return false;
}

#if ENABLED(DUAL_X_CARRIAGE) || ENABLED(DUAL_NOZZLE_DUPLICATION_MODE)
  bool extruder_duplication_enabled = false; // Used in Dual X mode 2
#endif

#if ENABLED(DUAL_X_CARRIAGE)

  #define DXC_FULL_CONTROL_MODE 0
  #define DXC_AUTO_PARK_MODE    1
  #define DXC_DUPLICATION_MODE  2

  static int dual_x_carriage_mode = DEFAULT_DUAL_X_CARRIAGE_MODE;

  static float x_home_pos(int extruder) {
    if (extruder == 0)
      return LOGICAL_X_POSITION(base_home_pos(X_AXIS));
    else
      /**
       * In dual carriage mode the extruder offset provides an override of the
       * second X-carriage offset when homed - otherwise X2_HOME_POS is used.
       * This allow soft recalibration of the second extruder offset position
       * without firmware reflash (through the M218 command).
       */
      return (hotend_offset[X_AXIS][1] > 0) ? hotend_offset[X_AXIS][1] : X2_HOME_POS;
  }

  static int x_home_dir(int extruder) {
    return (extruder == 0) ? X_HOME_DIR : X2_HOME_DIR;
  }

  static float inactive_extruder_x_pos = X2_MAX_POS; // used in mode 0 & 1
  static bool active_extruder_parked = false;        // used in mode 1 & 2
  static float raised_parked_position[NUM_AXIS];     // used in mode 1
  static millis_t delayed_move_time = 0;             // used in mode 1
  static float duplicate_extruder_x_offset = DEFAULT_DUPLICATION_X_OFFSET; // used in mode 2
  static float duplicate_extruder_temp_offset = 0;   // used in mode 2

#endif //DUAL_X_CARRIAGE

/**
 * Software endstops can be used to monitor the open end of
 * an axis that has a hardware endstop on the other end. Or
 * they can prevent axes from moving past endstops and grinding.
 *
 * To keep doing their job as the coordinate system changes,
 * the software endstop positions must be refreshed to remain
 * at the same positions relative to the machine.
 */
void update_software_endstops(AxisEnum axis) {
  float offs = LOGICAL_POSITION(0, axis);

  #if ENABLED(DUAL_X_CARRIAGE)
    if (axis == X_AXIS) {
      float dual_max_x = max(hotend_offset[X_AXIS][1], X2_MAX_POS);
      if (active_extruder != 0) {
        soft_endstop_min[X_AXIS] = X2_MIN_POS + offs;
        soft_endstop_max[X_AXIS] = dual_max_x + offs;
        return;
      }
      else if (dual_x_carriage_mode == DXC_DUPLICATION_MODE) {
        soft_endstop_min[X_AXIS] = base_min_pos(X_AXIS) + offs;
        soft_endstop_max[X_AXIS] = min(base_max_pos(X_AXIS), dual_max_x - duplicate_extruder_x_offset) + offs;
        return;
      }
    }
    else
  #endif
  {
    soft_endstop_min[axis] = base_min_pos(axis) + offs;
    soft_endstop_max[axis] = base_max_pos(axis) + offs;
  }

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOPAIR("For ", axis_codes[axis]);
      SERIAL_ECHOPAIR(" axis:\n home_offset = ", home_offset[axis]);
      SERIAL_ECHOPAIR("\n position_shift = ", position_shift[axis]);
      SERIAL_ECHOPAIR("\n soft_endstop_min = ", soft_endstop_min[axis]);
      SERIAL_ECHOLNPAIR("\n soft_endstop_max = ", soft_endstop_max[axis]);
    }
  #endif

  #if ENABLED(DELTA)
    if (axis == Z_AXIS)
      delta_clip_start_height = soft_endstop_max[axis] - delta_safe_distance_from_top();
  #endif

}

/**
 * Change the home offset for an axis, update the current
 * position and the software endstops to retain the same
 * relative distance to the new home.
 *
 * Since this changes the current_position, code should
 * call sync_plan_position soon after this.
 */
static void set_home_offset(AxisEnum axis, float v) {
  current_position[axis] += v - home_offset[axis];
  home_offset[axis] = v;
  update_software_endstops(axis);
}

/**
 * Set an axis' current position to its home position (after homing).
 *
 * For Core and Cartesian robots this applies one-to-one when an
 * individual axis has been homed.
 *
 * DELTA should wait until all homing is done before setting the XYZ
 * current_position to home, because homing is a single operation.
 * In the case where the axis positions are already known and previously
 * homed, DELTA could home to X or Y individually by moving either one
 * to the center. However, homing Z always homes XY and Z.
 *
 * SCARA should wait until all XY homing is done before setting the XY
 * current_position to home, because neither X nor Y is at home until
 * both are at home. Z can however be homed individually.
 * 
 */
static void set_axis_is_at_home(AxisEnum axis) {
  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOPAIR(">>> set_axis_is_at_home(", axis_codes[axis]);
      SERIAL_ECHOLNPGM(")");
    }
  #endif

  axis_known_position[axis] = axis_homed[axis] = true;

  position_shift[axis] = 0;
  update_software_endstops(axis);

  #if ENABLED(DUAL_X_CARRIAGE)
    if (axis == X_AXIS && (active_extruder != 0 || dual_x_carriage_mode == DXC_DUPLICATION_MODE)) {
      if (active_extruder != 0)
        current_position[X_AXIS] = x_home_pos(active_extruder);
      else
        current_position[X_AXIS] = LOGICAL_X_POSITION(base_home_pos(X_AXIS));
      update_software_endstops(X_AXIS);
      return;
    }
  #endif

  #if ENABLED(MORGAN_SCARA)

    /**
     * Morgan SCARA homes XY at the same time
     */
    if (axis == X_AXIS || axis == Y_AXIS) {

      float homeposition[XYZ];
      LOOP_XYZ(i) homeposition[i] = LOGICAL_POSITION(base_home_pos(i), i);

      // SERIAL_ECHOPAIR("homeposition X:", homeposition[X_AXIS]);
      // SERIAL_ECHOLNPAIR(" Y:", homeposition[Y_AXIS]);

      /**
       * Get Home position SCARA arm angles using inverse kinematics,
       * and calculate homing offset using forward kinematics
       */
      inverse_kinematics(homeposition);
      forward_kinematics_SCARA(delta[A_AXIS], delta[B_AXIS]);

      // SERIAL_ECHOPAIR("Cartesian X:", cartes[X_AXIS]);
      // SERIAL_ECHOLNPAIR(" Y:", cartes[Y_AXIS]);

      current_position[axis] = LOGICAL_POSITION(cartes[axis], axis);

      /**
       * SCARA home positions are based on configuration since the actual
       * limits are determined by the inverse kinematic transform.
       */
      soft_endstop_min[axis] = base_min_pos(axis); // + (cartes[axis] - base_home_pos(axis));
      soft_endstop_max[axis] = base_max_pos(axis); // + (cartes[axis] - base_home_pos(axis));
    }
    else
  #endif
  {
    current_position[axis] = LOGICAL_POSITION(base_home_pos(axis), axis);
  }

  /**
   * Z Probe Z Homing? Account for the probe's Z offset.
   */
  #if HAS_BED_PROBE && Z_HOME_DIR < 0
    if (axis == Z_AXIS) {
      #if HOMING_Z_WITH_PROBE

        current_position[Z_AXIS] -= zprobe_zoffset;

        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) {
            SERIAL_ECHOLNPGM("*** Z HOMED WITH PROBE (Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN) ***");
            SERIAL_ECHOLNPAIR("> zprobe_zoffset = ", zprobe_zoffset);
          }
        #endif

      #elif ENABLED(DEBUG_LEVELING_FEATURE)

        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("*** Z HOMED TO ENDSTOP (Z_MIN_PROBE_ENDSTOP) ***");

      #endif
    }
  #endif

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOPAIR("> home_offset[", axis_codes[axis]);
      SERIAL_ECHOLNPAIR("] = ", home_offset[axis]);
      DEBUG_POS("", current_position);
      SERIAL_ECHOPAIR("<<< set_axis_is_at_home(", axis_codes[axis]);
      SERIAL_ECHOLNPGM(")");
    }
  #endif
}

/**
 * Some planner shorthand inline functions
 */
inline float get_homing_bump_feedrate(AxisEnum axis) {
  int constexpr homing_bump_divisor[] = HOMING_BUMP_DIVISOR;
  int hbd = homing_bump_divisor[axis];
  if (hbd < 1) {
    hbd = 10;
    SERIAL_ECHO_START;
    SERIAL_ECHOLNPGM("Warning: Homing Bump Divisor < 1");
  }
  return homing_feedrate_mm_s[axis] / hbd;
}

//
// line_to_current_position
// Move the planner to the current position from wherever it last moved
// (or from wherever it has been told it is located).
//
inline void line_to_current_position() {
  planner.buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], feedrate_mm_s, active_extruder);
}

//
// line_to_destination
// Move the planner, not necessarily synced with current_position
//
inline void line_to_destination(float fr_mm_s) {
  planner.buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], fr_mm_s, active_extruder);
}
inline void line_to_destination() { line_to_destination(feedrate_mm_s); }

inline void set_current_to_destination() { memcpy(current_position, destination, sizeof(current_position)); }
inline void set_destination_to_current() { memcpy(destination, current_position, sizeof(destination)); }

#if IS_KINEMATIC
  /**
   * Calculate delta, start a line, and set current_position to destination
   */
  void prepare_uninterpolated_move_to_destination(const float fr_mm_s=0.0) {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("prepare_uninterpolated_move_to_destination", destination);
    #endif

    if ( current_position[X_AXIS] == destination[X_AXIS]
      && current_position[Y_AXIS] == destination[Y_AXIS]
      && current_position[Z_AXIS] == destination[Z_AXIS]
      && current_position[E_AXIS] == destination[E_AXIS]
    ) return;

    refresh_cmd_timeout();
    inverse_kinematics(destination);
    planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], destination[E_AXIS], MMS_SCALED(fr_mm_s ? fr_mm_s : feedrate_mm_s), active_extruder);
    set_current_to_destination();
  }
#endif // IS_KINEMATIC

/**
 *  Plan a move to (X, Y, Z) and set the current_position
 *  The final current_position may not be the one that was requested
 */
void do_blocking_move_to(const float &x, const float &y, const float &z, const float &fr_mm_s /*=0.0*/) {
  float old_feedrate_mm_s = feedrate_mm_s;

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) print_xyz(PSTR(">>> do_blocking_move_to"), NULL, x, y, z);
  #endif

  #if ENABLED(DELTA)

    feedrate_mm_s = fr_mm_s ? fr_mm_s : XY_PROBE_FEEDRATE_MM_S;

    set_destination_to_current();          // sync destination at the start

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("set_destination_to_current", destination);
    #endif

    // when in the danger zone
    if (current_position[Z_AXIS] > delta_clip_start_height) {
      if (z > delta_clip_start_height) {   // staying in the danger zone
        destination[X_AXIS] = x;           // move directly (uninterpolated)
        destination[Y_AXIS] = y;
        destination[Z_AXIS] = z;
        prepare_uninterpolated_move_to_destination(); // set_current_to_destination
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("danger zone move", current_position);
        #endif
        return;
      }
      else {
        destination[Z_AXIS] = delta_clip_start_height;
        prepare_uninterpolated_move_to_destination(); // set_current_to_destination
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("zone border move", current_position);
        #endif
      }
    }

    if (z > current_position[Z_AXIS]) {    // raising?
      destination[Z_AXIS] = z;
      prepare_uninterpolated_move_to_destination();   // set_current_to_destination
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) DEBUG_POS("z raise move", current_position);
      #endif
    }

    destination[X_AXIS] = x;
    destination[Y_AXIS] = y;
    prepare_move_to_destination();         // set_current_to_destination
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("xy move", current_position);
    #endif

    if (z < current_position[Z_AXIS]) {    // lowering?
      destination[Z_AXIS] = z;
      prepare_uninterpolated_move_to_destination();   // set_current_to_destination
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) DEBUG_POS("z lower move", current_position);
      #endif
    }

  #elif IS_SCARA

    set_destination_to_current();

    // If Z needs to raise, do it before moving XY
    if (destination[Z_AXIS] < z) {
      destination[Z_AXIS] = z;
      prepare_uninterpolated_move_to_destination(fr_mm_s ? fr_mm_s : homing_feedrate_mm_s[Z_AXIS]);
    }

    destination[X_AXIS] = x;
    destination[Y_AXIS] = y;
    prepare_uninterpolated_move_to_destination(fr_mm_s ? fr_mm_s : XY_PROBE_FEEDRATE_MM_S);

    // If Z needs to lower, do it after moving XY
    if (destination[Z_AXIS] > z) {
      destination[Z_AXIS] = z;
      prepare_uninterpolated_move_to_destination(fr_mm_s ? fr_mm_s : homing_feedrate_mm_s[Z_AXIS]);
    }

  #else

    // If Z needs to raise, do it before moving XY
    if (current_position[Z_AXIS] < z) {
      feedrate_mm_s = fr_mm_s ? fr_mm_s : homing_feedrate_mm_s[Z_AXIS];
      current_position[Z_AXIS] = z;
      line_to_current_position();
    }

    feedrate_mm_s = fr_mm_s ? fr_mm_s : XY_PROBE_FEEDRATE_MM_S;
    current_position[X_AXIS] = x;
    current_position[Y_AXIS] = y;
    line_to_current_position();

    // If Z needs to lower, do it after moving XY
    if (current_position[Z_AXIS] > z) {
      feedrate_mm_s = fr_mm_s ? fr_mm_s : homing_feedrate_mm_s[Z_AXIS];
      current_position[Z_AXIS] = z;
      line_to_current_position();
    }

  #endif

  stepper.synchronize();

  feedrate_mm_s = old_feedrate_mm_s;

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("<<< do_blocking_move_to");
  #endif
}
void do_blocking_move_to_x(const float &x, const float &fr_mm_s/*=0.0*/) {
  do_blocking_move_to(x, current_position[Y_AXIS], current_position[Z_AXIS], fr_mm_s);
}
void do_blocking_move_to_z(const float &z, const float &fr_mm_s/*=0.0*/) {
  do_blocking_move_to(current_position[X_AXIS], current_position[Y_AXIS], z, fr_mm_s);
}
void do_blocking_move_to_xy(const float &x, const float &y, const float &fr_mm_s/*=0.0*/) {
  do_blocking_move_to(x, y, current_position[Z_AXIS], fr_mm_s);
}

//
// Prepare to do endstop or probe moves
// with custom feedrates.
//
//  - Save current feedrates
//  - Reset the rate multiplier
//  - Reset the command timeout
//  - Enable the endstops (for endstop moves)
//
static void setup_for_endstop_or_probe_move() {
  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) DEBUG_POS("setup_for_endstop_or_probe_move", current_position);
  #endif
  saved_feedrate_mm_s = feedrate_mm_s;
  saved_feedrate_percentage = feedrate_percentage;
  feedrate_percentage = 100;
  refresh_cmd_timeout();
}

static void clean_up_after_endstop_or_probe_move() {
  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) DEBUG_POS("clean_up_after_endstop_or_probe_move", current_position);
  #endif
  feedrate_mm_s = saved_feedrate_mm_s;
  feedrate_percentage = saved_feedrate_percentage;
  refresh_cmd_timeout();
}

#if HAS_BED_PROBE
  /**
   * Raise Z to a minimum height to make room for a probe to move
   */
  inline void do_probe_raise(float z_raise) {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOPAIR("do_probe_raise(", z_raise);
        SERIAL_ECHOLNPGM(")");
      }
    #endif

    float z_dest = LOGICAL_Z_POSITION(z_raise);
    if (zprobe_zoffset < 0) z_dest -= zprobe_zoffset;

    if (z_dest > current_position[Z_AXIS])
      do_blocking_move_to_z(z_dest);
  }

#endif //HAS_BED_PROBE

#if ENABLED(Z_PROBE_ALLEN_KEY) || ENABLED(Z_PROBE_SLED) || HAS_PROBING_PROCEDURE || HOTENDS > 1 || ENABLED(NOZZLE_CLEAN_FEATURE) || ENABLED(NOZZLE_PARK_FEATURE)
  static bool axis_unhomed_error(const bool x, const bool y, const bool z) {
    const bool xx = x && !axis_homed[X_AXIS],
               yy = y && !axis_homed[Y_AXIS],
               zz = z && !axis_homed[Z_AXIS];
    if (xx || yy || zz) {
      SERIAL_ECHO_START;
      SERIAL_ECHOPGM(MSG_HOME " ");
      if (xx) SERIAL_ECHOPGM(MSG_X);
      if (yy) SERIAL_ECHOPGM(MSG_Y);
      if (zz) SERIAL_ECHOPGM(MSG_Z);
      SERIAL_ECHOLNPGM(" " MSG_FIRST);

      #if ENABLED(ULTRA_LCD)
        char message[3 * (LCD_WIDTH) + 1] = ""; // worst case is kana.utf with up to 3*LCD_WIDTH+1
        strcat_P(message, PSTR(MSG_HOME " "));
        if (xx) strcat_P(message, PSTR(MSG_X));
        if (yy) strcat_P(message, PSTR(MSG_Y));
        if (zz) strcat_P(message, PSTR(MSG_Z));
        strcat_P(message, PSTR(" " MSG_FIRST));
        lcd_setstatus(message);
      #endif
      return true;
    }
    return false;
  }
#endif

#if ENABLED(Z_PROBE_SLED)

  #ifndef SLED_DOCKING_OFFSET
    #define SLED_DOCKING_OFFSET 0
  #endif

  /**
   * Method to dock/undock a sled designed by Charles Bell.
   *
   * stow[in]     If false, move to MAX_X and engage the solenoid
   *              If true, move to MAX_X and release the solenoid
   */
  static void dock_sled(bool stow) {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOPAIR("dock_sled(", stow);
        SERIAL_ECHOLNPGM(")");
      }
    #endif

    // Dock sled a bit closer to ensure proper capturing
    do_blocking_move_to_x(X_MAX_POS + SLED_DOCKING_OFFSET - ((stow) ? 1 : 0));

    #if PIN_EXISTS(SLED)
      digitalWrite(SLED_PIN, !stow); // switch solenoid
    #endif
  }

#endif // Z_PROBE_SLED
#if ENABLED(Z_PROBE_ALLEN_KEY)
  void run_deploy_moves_script() {
    #if defined(Z_PROBE_ALLEN_KEY_DEPLOY_1_X) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_1_Y) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_1_Z)
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_1_X
        #define Z_PROBE_ALLEN_KEY_DEPLOY_1_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_1_Y
        #define Z_PROBE_ALLEN_KEY_DEPLOY_1_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_1_Z
        #define Z_PROBE_ALLEN_KEY_DEPLOY_1_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_1_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_DEPLOY_1_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_DEPLOY_1_X, Z_PROBE_ALLEN_KEY_DEPLOY_1_Y, Z_PROBE_ALLEN_KEY_DEPLOY_1_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_DEPLOY_1_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_DEPLOY_2_X) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_2_Y) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_2_Z)
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_2_X
        #define Z_PROBE_ALLEN_KEY_DEPLOY_2_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_2_Y
        #define Z_PROBE_ALLEN_KEY_DEPLOY_2_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_2_Z
        #define Z_PROBE_ALLEN_KEY_DEPLOY_2_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_2_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_DEPLOY_2_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_DEPLOY_2_X, Z_PROBE_ALLEN_KEY_DEPLOY_2_Y, Z_PROBE_ALLEN_KEY_DEPLOY_2_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_DEPLOY_2_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_DEPLOY_3_X) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_3_Y) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_3_Z)
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_3_X
        #define Z_PROBE_ALLEN_KEY_DEPLOY_3_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_3_Y
        #define Z_PROBE_ALLEN_KEY_DEPLOY_3_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_3_Z
        #define Z_PROBE_ALLEN_KEY_DEPLOY_3_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_3_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_DEPLOY_3_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_DEPLOY_3_X, Z_PROBE_ALLEN_KEY_DEPLOY_3_Y, Z_PROBE_ALLEN_KEY_DEPLOY_3_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_DEPLOY_3_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_DEPLOY_4_X) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_4_Y) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_4_Z)
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_4_X
        #define Z_PROBE_ALLEN_KEY_DEPLOY_4_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_4_Y
        #define Z_PROBE_ALLEN_KEY_DEPLOY_4_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_4_Z
        #define Z_PROBE_ALLEN_KEY_DEPLOY_4_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_4_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_DEPLOY_4_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_DEPLOY_4_X, Z_PROBE_ALLEN_KEY_DEPLOY_4_Y, Z_PROBE_ALLEN_KEY_DEPLOY_4_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_DEPLOY_4_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_DEPLOY_5_X) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_5_Y) || defined(Z_PROBE_ALLEN_KEY_DEPLOY_5_Z)
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_5_X
        #define Z_PROBE_ALLEN_KEY_DEPLOY_5_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_5_Y
        #define Z_PROBE_ALLEN_KEY_DEPLOY_5_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_5_Z
        #define Z_PROBE_ALLEN_KEY_DEPLOY_5_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_DEPLOY_5_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_DEPLOY_5_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_DEPLOY_5_X, Z_PROBE_ALLEN_KEY_DEPLOY_5_Y, Z_PROBE_ALLEN_KEY_DEPLOY_5_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_DEPLOY_5_FEEDRATE));
    #endif
  }
  void run_stow_moves_script() {
    #if defined(Z_PROBE_ALLEN_KEY_STOW_1_X) || defined(Z_PROBE_ALLEN_KEY_STOW_1_Y) || defined(Z_PROBE_ALLEN_KEY_STOW_1_Z)
      #ifndef Z_PROBE_ALLEN_KEY_STOW_1_X
        #define Z_PROBE_ALLEN_KEY_STOW_1_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_1_Y
        #define Z_PROBE_ALLEN_KEY_STOW_1_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_1_Z
        #define Z_PROBE_ALLEN_KEY_STOW_1_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_1_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_STOW_1_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_STOW_1_X, Z_PROBE_ALLEN_KEY_STOW_1_Y, Z_PROBE_ALLEN_KEY_STOW_1_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_STOW_1_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_STOW_2_X) || defined(Z_PROBE_ALLEN_KEY_STOW_2_Y) || defined(Z_PROBE_ALLEN_KEY_STOW_2_Z)
      #ifndef Z_PROBE_ALLEN_KEY_STOW_2_X
        #define Z_PROBE_ALLEN_KEY_STOW_2_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_2_Y
        #define Z_PROBE_ALLEN_KEY_STOW_2_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_2_Z
        #define Z_PROBE_ALLEN_KEY_STOW_2_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_2_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_STOW_2_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_STOW_2_X, Z_PROBE_ALLEN_KEY_STOW_2_Y, Z_PROBE_ALLEN_KEY_STOW_2_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_STOW_2_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_STOW_3_X) || defined(Z_PROBE_ALLEN_KEY_STOW_3_Y) || defined(Z_PROBE_ALLEN_KEY_STOW_3_Z)
      #ifndef Z_PROBE_ALLEN_KEY_STOW_3_X
        #define Z_PROBE_ALLEN_KEY_STOW_3_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_3_Y
        #define Z_PROBE_ALLEN_KEY_STOW_3_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_3_Z
        #define Z_PROBE_ALLEN_KEY_STOW_3_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_3_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_STOW_3_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_STOW_3_X, Z_PROBE_ALLEN_KEY_STOW_3_Y, Z_PROBE_ALLEN_KEY_STOW_3_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_STOW_3_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_STOW_4_X) || defined(Z_PROBE_ALLEN_KEY_STOW_4_Y) || defined(Z_PROBE_ALLEN_KEY_STOW_4_Z)
      #ifndef Z_PROBE_ALLEN_KEY_STOW_4_X
        #define Z_PROBE_ALLEN_KEY_STOW_4_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_4_Y
        #define Z_PROBE_ALLEN_KEY_STOW_4_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_4_Z
        #define Z_PROBE_ALLEN_KEY_STOW_4_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_4_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_STOW_4_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_STOW_4_X, Z_PROBE_ALLEN_KEY_STOW_4_Y, Z_PROBE_ALLEN_KEY_STOW_4_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_STOW_4_FEEDRATE));
    #endif
    #if defined(Z_PROBE_ALLEN_KEY_STOW_5_X) || defined(Z_PROBE_ALLEN_KEY_STOW_5_Y) || defined(Z_PROBE_ALLEN_KEY_STOW_5_Z)
      #ifndef Z_PROBE_ALLEN_KEY_STOW_5_X
        #define Z_PROBE_ALLEN_KEY_STOW_5_X current_position[X_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_5_Y
        #define Z_PROBE_ALLEN_KEY_STOW_5_Y current_position[Y_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_5_Z
        #define Z_PROBE_ALLEN_KEY_STOW_5_Z current_position[Z_AXIS]
      #endif
      #ifndef Z_PROBE_ALLEN_KEY_STOW_5_FEEDRATE
        #define Z_PROBE_ALLEN_KEY_STOW_5_FEEDRATE 0.0
      #endif
      do_blocking_move_to(Z_PROBE_ALLEN_KEY_STOW_5_X, Z_PROBE_ALLEN_KEY_STOW_5_Y, Z_PROBE_ALLEN_KEY_STOW_5_Z, MMM_TO_MMS(Z_PROBE_ALLEN_KEY_STOW_5_FEEDRATE));
    #endif
  }
#endif

#if HAS_BED_PROBE

 // TRIGGERED_WHEN_STOWED_TEST can easily be extended to servo probes, ... if needed.
  #if ENABLED(PROBE_IS_TRIGGERED_WHEN_STOWED_TEST)
    #if ENABLED(Z_MIN_PROBE_ENDSTOP)
      #define _TRIGGERED_WHEN_STOWED_TEST (READ(Z_MIN_PROBE_PIN) != Z_MIN_PROBE_ENDSTOP_INVERTING)
    #else
      #define _TRIGGERED_WHEN_STOWED_TEST (READ(Z_MIN_PIN) != Z_MIN_ENDSTOP_INVERTING)
    #endif
  #endif

  #define DEPLOY_PROBE() set_probe_deployed(true)
  #define STOW_PROBE() set_probe_deployed(false)

  #if ENABLED(BLTOUCH)
    FORCE_INLINE void set_bltouch_deployed(const bool &deploy) {
      servo[Z_ENDSTOP_SERVO_NR].move(deploy ? BLTOUCH_DEPLOY : BLTOUCH_STOW);
    }
  #endif

  // returns false for ok and true for failure
  static bool set_probe_deployed(bool deploy) {

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        DEBUG_POS("set_probe_deployed", current_position);
        SERIAL_ECHOLNPAIR("deploy: ", deploy);
      }
    #endif

    if (endstops.z_probe_enabled == deploy) return false;

    // Make room for probe
    do_probe_raise(_Z_CLEARANCE_DEPLOY_PROBE);

    // When deploying make sure BLTOUCH is not already triggered
    #if ENABLED(BLTOUCH)
      if (deploy && TEST_BLTOUCH()) { stop(); return true; }
    #endif

    #if ENABLED(Z_PROBE_SLED)
      if (axis_unhomed_error(true, false, false)) { stop(); return true; }
    #elif ENABLED(Z_PROBE_ALLEN_KEY)
      if (axis_unhomed_error(true, true,  true )) { stop(); return true; }
    #endif

    float oldXpos = current_position[X_AXIS],
          oldYpos = current_position[Y_AXIS];

    #ifdef _TRIGGERED_WHEN_STOWED_TEST

      // If endstop is already false, the Z probe is deployed
      if (_TRIGGERED_WHEN_STOWED_TEST == deploy) {     // closed after the probe specific actions.
                                                       // Would a goto be less ugly?
        //while (!_TRIGGERED_WHEN_STOWED_TEST) idle(); // would offer the opportunity
                                                       // for a triggered when stowed manual probe.

        if (!deploy) endstops.enable_z_probe(false); // Switch off triggered when stowed probes early
                                                     // otherwise an Allen-Key probe can't be stowed.
    #endif

        #if ENABLED(Z_PROBE_SLED)

          dock_sled(!deploy);

        #elif HAS_Z_SERVO_ENDSTOP && DISABLED(BLTOUCH)

          servo[Z_ENDSTOP_SERVO_NR].move(z_servo_angle[deploy ? 0 : 1]);

        #elif ENABLED(Z_PROBE_ALLEN_KEY)

          deploy ? run_deploy_moves_script() : run_stow_moves_script();

        #endif

    #ifdef _TRIGGERED_WHEN_STOWED_TEST
      } // _TRIGGERED_WHEN_STOWED_TEST == deploy

      if (_TRIGGERED_WHEN_STOWED_TEST == deploy) { // State hasn't changed?

        if (IsRunning()) {
          SERIAL_ERROR_START;
          SERIAL_ERRORLNPGM("Z-Probe failed");
          LCD_ALERTMESSAGEPGM("Err: ZPROBE");
        }
        stop();
        return true;

      } // _TRIGGERED_WHEN_STOWED_TEST == deploy

    #endif

    do_blocking_move_to(oldXpos, oldYpos, current_position[Z_AXIS]); // return to position before deploy
    endstops.enable_z_probe(deploy);
    return false;
  }

  static void do_probe_move(float z, float fr_mm_m) {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS(">>> do_probe_move", current_position);
    #endif

    // Deploy BLTouch at the start of any probe
    #if ENABLED(BLTOUCH)
      set_bltouch_deployed(true);
    #endif

    // Move down until probe triggered
    do_blocking_move_to_z(LOGICAL_Z_POSITION(z), MMM_TO_MMS(fr_mm_m));

    // Retract BLTouch immediately after a probe
    #if ENABLED(BLTOUCH)
      set_bltouch_deployed(false);
    #endif

    // Clear endstop flags
    endstops.hit_on_purpose();

    // Tell the planner where we actually are
    planner.sync_from_steppers();

    // Get Z where the steppers were interrupted
    set_current_from_steppers_for_axis(Z_AXIS);

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("<<< do_probe_move", current_position);
    #endif
  }

  // Do a single Z probe and return with current_position[Z_AXIS]
  // at the height where the probe triggered.
  static float run_z_probe() {

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS(">>> run_z_probe", current_position);
    #endif

    // Prevent stepper_inactive_time from running out and EXTRUDER_RUNOUT_PREVENT from extruding
    refresh_cmd_timeout();

    #if ENABLED(PROBE_DOUBLE_TOUCH)

      // Do a first probe at the fast speed
      do_probe_move(-(Z_MAX_LENGTH) - 10, Z_PROBE_SPEED_FAST);

      #if ENABLED(DEBUG_LEVELING_FEATURE)
        float first_probe_z = current_position[Z_AXIS];
        if (DEBUGGING(LEVELING))
          SERIAL_ECHOPAIR("1st Probe Z:", first_probe_z);
      #endif

      // move up by the bump distance
      do_blocking_move_to_z(current_position[Z_AXIS] + home_bump_mm(Z_AXIS), MMM_TO_MMS(Z_PROBE_SPEED_FAST));

    #else

      // If the nozzle is above the travel height then
      // move down quickly before doing the slow probe
      float z = LOGICAL_Z_POSITION(Z_CLEARANCE_BETWEEN_PROBES);
      if (z < current_position[Z_AXIS])
        do_blocking_move_to_z(z, MMM_TO_MMS(Z_PROBE_SPEED_FAST));

    #endif

    // move down slowly to find bed
    do_probe_move(-(Z_MAX_LENGTH) - 10, Z_PROBE_SPEED_SLOW);

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("<<< run_z_probe", current_position);
    #endif

    // Debug: compare probe heights
    #if ENABLED(PROBE_DOUBLE_TOUCH) && ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOPAIR("2nd Probe Z:", current_position[Z_AXIS]);
        SERIAL_ECHOLNPAIR(" Discrepancy:", first_probe_z - current_position[Z_AXIS]);
      }
    #endif
    return current_position[Z_AXIS];
  }

  //
  // - Move to the given XY
  // - Deploy the probe, if not already deployed
  // - Probe the bed, get the Z position
  // - Depending on the 'stow' flag
  //   - Stow the probe, or
  //   - Raise to the BETWEEN height
  // - Return the probed Z position
  //
  static float probe_pt(const float &x, const float &y, bool stow = true, int verbose_level = 1) {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOPAIR(">>> probe_pt(", x);
        SERIAL_ECHOPAIR(", ", y);
        SERIAL_ECHOPAIR(", ", stow ? "stow" : "no stow");
        SERIAL_ECHOLNPGM(")");
        DEBUG_POS("", current_position);
      }
    #endif

    float old_feedrate_mm_s = feedrate_mm_s;

    // Ensure a minimum height before moving the probe
    do_probe_raise(Z_CLEARANCE_BETWEEN_PROBES);

    // Move to the XY where we shall probe
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOPAIR("> do_blocking_move_to_xy(", x - (X_PROBE_OFFSET_FROM_EXTRUDER));
        SERIAL_ECHOPAIR(", ", y - (Y_PROBE_OFFSET_FROM_EXTRUDER));
        SERIAL_ECHOLNPGM(")");
      }
    #endif

    feedrate_mm_s = XY_PROBE_FEEDRATE_MM_S;

    // Move the probe to the given XY
    do_blocking_move_to_xy(x - (X_PROBE_OFFSET_FROM_EXTRUDER), y - (Y_PROBE_OFFSET_FROM_EXTRUDER));

    if (DEPLOY_PROBE()) return NAN;

    float measured_z = run_z_probe();

    if (!stow)
      do_probe_raise(Z_CLEARANCE_BETWEEN_PROBES);
    else
      if (STOW_PROBE()) return NAN;

    if (verbose_level > 2) {
      SERIAL_PROTOCOLPGM("Bed X: ");
      SERIAL_PROTOCOL_F(x, 3);
      SERIAL_PROTOCOLPGM(" Y: ");
      SERIAL_PROTOCOL_F(y, 3);
      SERIAL_PROTOCOLPGM(" Z: ");
      SERIAL_PROTOCOL_F(measured_z, 3);
      SERIAL_EOL;
    }

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("<<< probe_pt");
    #endif

    feedrate_mm_s = old_feedrate_mm_s;

    return measured_z;
  }

#endif // HAS_BED_PROBE

#if PLANNER_LEVELING
  /**
   * Turn bed leveling on or off, fixing the current
   * position as-needed.
   *
   * Disable: Current position = physical position
   *  Enable: Current position = "unleveled" physical position
   */
  void set_bed_leveling_enabled(bool enable=true) {
    #if ENABLED(MESH_BED_LEVELING)

      if (!enable && mbl.active())
        current_position[Z_AXIS] +=
          mbl.get_z(RAW_CURRENT_POSITION(X_AXIS), RAW_CURRENT_POSITION(Y_AXIS)) - (MESH_HOME_SEARCH_Z);

      mbl.set_active(enable && mbl.has_mesh()); // was set_has_mesh(). Is this not correct?

    #elif HAS_ABL

      if (enable != planner.abl_enabled) {
        planner.abl_enabled = !planner.abl_enabled;
        if (!planner.abl_enabled)
          set_current_from_steppers_for_axis(
            #if ABL_PLANAR
              ALL_AXES
            #else
              Z_AXIS
            #endif
          );
        else
          planner.unapply_leveling(current_position);
      }

    #endif
  }


  /**
   * Reset calibration results to zero.
   */
  void reset_bed_level() {
    #if ENABLED(MESH_BED_LEVELING)
      if (mbl.has_mesh()) {
        set_bed_leveling_enabled(false);
        mbl.reset();
        mbl.set_has_mesh(false);
      }
    #else
      planner.abl_enabled = false;
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("reset_bed_level");
      #endif
      #if ABL_PLANAR
        planner.bed_level_matrix.set_to_identity();
      #elif ENABLED(AUTO_BED_LEVELING_BILINEAR)
        for (uint8_t x = 0; x < ABL_GRID_POINTS_X; x++)
          for (uint8_t y = 0; y < ABL_GRID_POINTS_Y; y++)
            bed_level_grid[x][y] = 1000.0;
      #endif
    #endif
  }

#endif // PLANNER_LEVELING

#if ENABLED(AUTO_BED_LEVELING_BILINEAR)

  /**
   * Extrapolate a single point from its neighbors
   */
  static void extrapolate_one_point(uint8_t x, uint8_t y, int8_t xdir, int8_t ydir) {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOPGM("Extrapolate [");
        if (x < 10) SERIAL_CHAR(' ');
        SERIAL_ECHO((int)x);
        SERIAL_CHAR(xdir ? (xdir > 0 ? '+' : '-') : ' ');
        SERIAL_CHAR(' ');
        if (y < 10) SERIAL_CHAR(' ');
        SERIAL_ECHO((int)y);
        SERIAL_CHAR(ydir ? (ydir > 0 ? '+' : '-') : ' ');
        SERIAL_ECHOLN(']');
      }
    #endif
    if (bed_level_grid[x][y] < 999.0) {
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM(" (done)");
      #endif
      return;  // Don't overwrite good values.
    }

    // Get X neighbors, Y neighbors, and XY neighbors
    float a1 = bed_level_grid[x + xdir][y], a2 = bed_level_grid[x + xdir * 2][y],
          b1 = bed_level_grid[x][y + ydir], b2 = bed_level_grid[x][y + ydir * 2],
          c1 = bed_level_grid[x + xdir][y + ydir], c2 = bed_level_grid[x + xdir * 2][y + ydir * 2];

    // Treat far unprobed points as zero, near as equal to far
    if (a2 > 999.0) a2 = 0.0; if (a1 > 999.0) a1 = a2;
    if (b2 > 999.0) b2 = 0.0; if (b1 > 999.0) b1 = b2;
    if (c2 > 999.0) c2 = 0.0; if (c1 > 999.0) c1 = c2;

    float a = 2 * a1 - a2, b = 2 * b1 - b2, c = 2 * c1 - c2;

    // Take the average intstead of the median
    bed_level_grid[x][y] = (a + b + c) / 3.0;

    // Median is robust (ignores outliers).
    // bed_level_grid[x][y] = (a < b) ? ((b < c) ? b : (c < a) ? a : c)
    //                                : ((c < b) ? b : (a < c) ? a : c);
  }

  #define EXTRAPOLATE_FROM_EDGE

  #if ENABLED(EXTRAPOLATE_FROM_EDGE)
    #if ABL_GRID_POINTS_X < ABL_GRID_POINTS_Y
      #define HALF_IN_X
    #elif ABL_GRID_POINTS_Y < ABL_GRID_POINTS_X
      #define HALF_IN_Y
    #endif
  #endif

  /**
   * Fill in the unprobed points (corners of circular print surface)
   * using linear extrapolation, away from the center.
   */
  static void extrapolate_unprobed_bed_level() {
    #ifdef HALF_IN_X
      const uint8_t ctrx2 = 0, xlen = ABL_GRID_POINTS_X - 1;
    #else
      const uint8_t ctrx1 = (ABL_GRID_POINTS_X - 1) / 2, // left-of-center
                    ctrx2 = ABL_GRID_POINTS_X / 2,       // right-of-center
                    xlen = ctrx1;
    #endif

    #ifdef HALF_IN_Y
      const uint8_t ctry2 = 0, ylen = ABL_GRID_POINTS_Y - 1;
    #else
      const uint8_t ctry1 = (ABL_GRID_POINTS_Y - 1) / 2, // top-of-center
                    ctry2 = ABL_GRID_POINTS_Y / 2,       // bottom-of-center
                    ylen = ctry1;
    #endif

    for (uint8_t xo = 0; xo <= xlen; xo++)
      for (uint8_t yo = 0; yo <= ylen; yo++) {
        uint8_t x2 = ctrx2 + xo, y2 = ctry2 + yo;
        #ifndef HALF_IN_X
          uint8_t x1 = ctrx1 - xo;
        #endif
        #ifndef HALF_IN_Y
          uint8_t y1 = ctry1 - yo;
          #ifndef HALF_IN_X
            extrapolate_one_point(x1, y1, +1, +1);   //  left-below + +
          #endif
          extrapolate_one_point(x2, y1, -1, +1);     // right-below - +
        #endif
        #ifndef HALF_IN_X
          extrapolate_one_point(x1, y2, +1, -1);     //  left-above + -
        #endif
        extrapolate_one_point(x2, y2, -1, -1);       // right-above - -
      }

  }

  /**
   * Print calibration results for plotting or manual frame adjustment.
   */
  static void print_bed_level() {
    SERIAL_ECHOPGM("Bilinear Leveling Grid:\n ");
    for (uint8_t x = 0; x < ABL_GRID_POINTS_X; x++) {
      SERIAL_PROTOCOLPGM("    ");
      if (x < 10) SERIAL_PROTOCOLCHAR(' ');
      SERIAL_PROTOCOL((int)x);
    }
    SERIAL_EOL;
    for (uint8_t y = 0; y < ABL_GRID_POINTS_Y; y++) {
      if (y < 9) SERIAL_PROTOCOLCHAR(' ');
      SERIAL_PROTOCOL(y);
      for (uint8_t x = 0; x < ABL_GRID_POINTS_X; x++) {
        SERIAL_PROTOCOLCHAR(' ');
        float offset = bed_level_grid[x][y];
        if (offset < 999.0) {
          if (offset > 0) SERIAL_CHAR('+');
          SERIAL_PROTOCOL_F(offset, 2);
        }
        else
          SERIAL_PROTOCOLPGM(" ====");
      }
      SERIAL_EOL;
    }
    SERIAL_EOL;
  }

#endif // AUTO_BED_LEVELING_BILINEAR


#ifdef G38_2_3

#define G38_minimum_move  0.0275   // minimum distance in mm that will produce a move (determined using the print statement in check_move)

bool check_move()  //checks that at least one of the axis in the command line has an actual move
                   // motion planner only does moves of 0.001mm and larger
{
	
  bool move_flag = false;
  for(int8_t i=0; i < 3; i++) {
/* debug used to determine prints
		SERIAL_PROTOCOLPGM("axis: ");
		SERIAL_PROTOCOL(axis_codes[i]);
		SERIAL_PROTOCOLPGM("  code_seen :  ");
		SERIAL_PROTOCOL(code_seen(axis_codes[i]));
		SERIAL_PROTOCOLPGM("  destination : ");
		SERIAL_PROTOCOL(destination[i]);
		SERIAL_PROTOCOLPGM("  current : ");
		SERIAL_PROTOCOL(current_position[i]);
		SERIAL_PROTOCOLPGM("  dif x 1000 : ");
		SERIAL_PROTOCOLLN((destination[i] - current_position[i]) * 1000);
 */		
  if (code_seen(axis_codes[i]) && (fabs(destination[i] - current_position[i]) >= G38_minimum_move)) move_flag = true ;
/*
 ??  0.0275mm produced a move on my machine along with an updated current position. 
     0.0265mm did NOT produce a move and did NOT change the current position
     this is very different than the 0.001 in the planner.
       0.001" is .0254mm so maybe the 0.0275 observed comes from digital storage limitations/conversion/rounding
 */
  }
  return move_flag;
}


static void G38_run_probe(bool *G38_pass_fail) {
 
  G38_flag = true;  //tell the interrupt handler that we're doing a G38 probe
  *G38_pass_fail = false;  
  
#ifdef X_HOME_BUMP_MM
#ifdef Y_HOME_BUMP_MM
#ifdef Z_HOME_BUMP_MM
  float G38_X_retract_mm = home_bump_mm(X_AXIS);
  float G38_Y_retract_mm = home_bump_mm(Y_AXIS);
  float G38_Z_retract_mm = home_bump_mm(Z_AXIS);
  
#else
    
  float G38_X_retract_mm = 5;
  float G38_Y_retract_mm = 5;
  float G38_Z_retract_mm = 2;

#endif
#endif  
#endif  
  
  // only retract the axis if the axis is in the command
  if( (!code_seen('X') || (code_value_axis_units(X_AXIS) == 0)))  G38_X_retract_mm = 0;   
  if( (!code_seen('Y') || (code_value_axis_units(Y_AXIS) == 0)))  G38_Y_retract_mm = 0;
  if( (!code_seen('Z') || (code_value_axis_units(Z_AXIS) == 0)))  G38_Z_retract_mm = 0;

  // change the direction of the retract if needed
  if ((destination[X_AXIS] - current_position[X_AXIS])>0) G38_X_retract_mm = -G38_X_retract_mm;
  if ((destination[Y_AXIS] - current_position[Y_AXIS])>0) G38_Y_retract_mm = -G38_Y_retract_mm;
  if ((destination[Z_AXIS] - current_position[Z_AXIS])>0) G38_Z_retract_mm = -G38_Z_retract_mm;

  
  stepper.synchronize();  // wait until the machine is idle
  
  bool save_endstops = endstops.enabled;    //remember state of endstops so we can retore them at the end
  endstops.enable(true);
    
  // move until you reach the destination or hit an endstop or hit the target
  // it's an error unless have hit the target
  G38_flag_pass = false;
  *G38_pass_fail = false;
  
  planner.buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], feedrate_mm_s, active_extruder);
  stepper.synchronize();

  // we have to let the planner know where we are right now as it is not where we said to go.
  //  and we need to update current_position[axis]
  current_position[X_AXIS] = stepper.get_axis_position_mm(X_AXIS);
  current_position[Y_AXIS] = stepper.get_axis_position_mm(Y_AXIS);
  current_position[Z_AXIS] = stepper.get_axis_position_mm(Z_AXIS);
  planner.set_position_mm(current_position[X_AXIS], current_position[Y_AXIS] , current_position[Z_AXIS] , current_position[E_AXIS]);

  *G38_pass_fail = G38_flag_pass ;  // only care if hit target on the first move
    
  if (*G38_pass_fail) {  // no sense in doing the remaining moves if we didn't hit the endstop  
    // move away the retract distance
    float xPosition = current_position[X_AXIS] + G38_X_retract_mm;
    float yPosition = current_position[Y_AXIS] + G38_Y_retract_mm;
    float zPosition = current_position[Z_AXIS] + G38_Z_retract_mm;
     

  
    // disable endstops on retract otherwise sometimes can't get away  
    endstops.enable(false);
    G38_flag = false; 
    
    planner.buffer_line(xPosition, yPosition , zPosition , current_position[E_AXIS], feedrate_mm_s/4, active_extruder);
    stepper.synchronize();


    // move back slowly
    xPosition -= G38_X_retract_mm * 2;
    yPosition -= G38_Y_retract_mm * 2;
    zPosition -= G38_Z_retract_mm * 2;
 

    // enable endstops on move back
    endstops.enable(true);
    G38_flag = true; 
    
    planner.buffer_line(xPosition, yPosition , zPosition , current_position[E_AXIS], feedrate_mm_s/4, active_extruder);
    stepper.synchronize();

    // we have to let the planner know where we are right now as it is not where we said to go.
    //  and we need to update current_position[axis]
    current_position[X_AXIS] = stepper.get_axis_position_mm(X_AXIS);
    current_position[Y_AXIS] = stepper.get_axis_position_mm(Y_AXIS);
    current_position[Z_AXIS] = stepper.get_axis_position_mm(Z_AXIS);
    planner.set_position_mm(current_position[X_AXIS], current_position[Y_AXIS] , current_position[Z_AXIS] , current_position[E_AXIS]);
    
  }  
  
//  clean_up_after_endstop_move();

  endstops.enable(save_endstops);   //restore endstops to same state as when we started

  endstops.hit_on_purpose();
  G38_flag = false;  //tell the interrupt handler that we're done
  
}

#endif  //G38_2_3


/**
 * Home an individual linear axis
 */
static void do_homing_move(const AxisEnum axis, float distance, float fr_mm_s=0.0) {

  #if HOMING_Z_WITH_PROBE && ENABLED(BLTOUCH)
    bool deploy_bltouch = (axis == Z_AXIS && distance < 0);
    if (deploy_bltouch) set_bltouch_deployed(true);
  #endif

  // Tell the planner we're at Z=0
  current_position[axis] = 0;

  #if IS_SCARA
    SYNC_PLAN_POSITION_KINEMATIC();
    current_position[axis] = distance;
    inverse_kinematics(current_position);
    planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], current_position[E_AXIS], fr_mm_s ? fr_mm_s : homing_feedrate_mm_s[axis], active_extruder);
  #else
    sync_plan_position();
    current_position[axis] = distance;
    planner.buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], fr_mm_s ? fr_mm_s : homing_feedrate_mm_s[axis], active_extruder);
  #endif

  stepper.synchronize();

  #if HOMING_Z_WITH_PROBE && ENABLED(BLTOUCH)
    if (deploy_bltouch) set_bltouch_deployed(false);
  #endif

  endstops.hit_on_purpose();
}

/**
 * Home an individual "raw axis" to its endstop.
 * This applies to XYZ on Cartesian and Core robots, and
 * to the individual ABC steppers on DELTA and SCARA.
 *
 * At the end of the procedure the axis is marked as
 * homed and the current position of that axis is updated.
 * Kinematic robots should wait till all axes are homed
 * before updating the current position.
 */

#define HOMEAXIS(LETTER) homeaxis(LETTER##_AXIS)

static void homeaxis(AxisEnum axis) {

  #if IS_SCARA
    // Only Z homing (with probe) is permitted
    if (axis != Z_AXIS) { BUZZ(100, 880); return; }
  #else
    #define CAN_HOME(A) \
      (axis == A##_AXIS && ((A##_MIN_PIN > -1 && A##_HOME_DIR < 0) || (A##_MAX_PIN > -1 && A##_HOME_DIR > 0)))
    if (!CAN_HOME(X) && !CAN_HOME(Y) && !CAN_HOME(Z)) return;
  #endif

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOPAIR(">>> homeaxis(", axis_codes[axis]);
      SERIAL_ECHOLNPGM(")");
    }
  #endif

  int axis_home_dir =
    #if ENABLED(DUAL_X_CARRIAGE)
      (axis == X_AXIS) ? x_home_dir(active_extruder) :
    #endif
    home_dir(axis);

  // Homing Z towards the bed? Deploy the Z probe or endstop.
  #if HOMING_Z_WITH_PROBE
    if (axis == Z_AXIS && DEPLOY_PROBE()) return;
  #endif

  // Set a flag for Z motor locking
  #if ENABLED(Z_DUAL_ENDSTOPS)
    if (axis == Z_AXIS) stepper.set_homing_flag(true);
  #endif

  // Fast move towards endstop until triggered
  do_homing_move(axis, 1.5 * max_length(axis) * axis_home_dir);

  // When homing Z with probe respect probe clearance
  const float bump = axis_home_dir * (
    #if HOMING_Z_WITH_PROBE
      (axis == Z_AXIS) ? max(Z_CLEARANCE_BETWEEN_PROBES, home_bump_mm(Z_AXIS)) :
    #endif
    home_bump_mm(axis)
  );

  // If a second homing move is configured...
  if (bump) {
    // Move away from the endstop by the axis HOME_BUMP_MM
    do_homing_move(axis, -bump);
    // Slow move towards endstop until triggered
    do_homing_move(axis, 2 * bump, get_homing_bump_feedrate(axis));
  }

  #if ENABLED(Z_DUAL_ENDSTOPS)
    if (axis == Z_AXIS) {
      float adj = fabs(z_endstop_adj);
      bool lockZ1;
      if (axis_home_dir > 0) {
        adj = -adj;
        lockZ1 = (z_endstop_adj > 0);
      }
      else
        lockZ1 = (z_endstop_adj < 0);

      if (lockZ1) stepper.set_z_lock(true); else stepper.set_z2_lock(true);

      // Move to the adjusted endstop height
      do_homing_move(axis, adj);

      if (lockZ1) stepper.set_z_lock(false); else stepper.set_z2_lock(false);
      stepper.set_homing_flag(false);
    } // Z_AXIS
  #endif

  #if IS_SCARA

    set_axis_is_at_home(axis);
    SYNC_PLAN_POSITION_KINEMATIC();

  #elif ENABLED(DELTA)

    // Delta has already moved all three towers up in G28
    // so here it re-homes each tower in turn.
    // Delta homing treats the axes as normal linear axes.

    // retrace by the amount specified in endstop_adj
    if (endstop_adj[axis] * Z_HOME_DIR < 0) {
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) {
          SERIAL_ECHOPAIR("> endstop_adj = ", endstop_adj[axis] * Z_HOME_DIR);
          DEBUG_POS("", current_position);
        }
      #endif
      do_homing_move(axis, endstop_adj[axis]);
    }

  #else

    // For cartesian/core machines,
    // set the axis to its home position
    set_axis_is_at_home(axis);
    sync_plan_position();

    destination[axis] = current_position[axis];

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("> AFTER set_axis_is_at_home", current_position);
    #endif

  #endif

  // Put away the Z probe
  #if HOMING_Z_WITH_PROBE
    if (axis == Z_AXIS && STOW_PROBE()) return;
  #endif

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOPAIR("<<< homeaxis(", axis_codes[axis]);
      SERIAL_ECHOLNPGM(")");
    }
  #endif
} // homeaxis()

#if ENABLED(FWRETRACT)

  void retract(bool retracting, bool swapping = false) {

    if (retracting == retracted[active_extruder]) return;

    float old_feedrate_mm_s = feedrate_mm_s;

    set_destination_to_current();

    if (retracting) {

      feedrate_mm_s = retract_feedrate_mm_s;
      current_position[E_AXIS] += (swapping ? retract_length_swap : retract_length) / volumetric_multiplier[active_extruder];
      sync_plan_position_e();
      prepare_move_to_destination();

      if (retract_zlift > 0.01) {
        current_position[Z_AXIS] -= retract_zlift;
        SYNC_PLAN_POSITION_KINEMATIC();
        prepare_move_to_destination();
      }
    }
    else {

      if (retract_zlift > 0.01) {
        current_position[Z_AXIS] += retract_zlift;
        SYNC_PLAN_POSITION_KINEMATIC();
      }

      feedrate_mm_s = retract_recover_feedrate_mm_s;
      float move_e = swapping ? retract_length_swap + retract_recover_length_swap : retract_length + retract_recover_length;
      current_position[E_AXIS] -= move_e / volumetric_multiplier[active_extruder];
      sync_plan_position_e();
      prepare_move_to_destination();
    }

    feedrate_mm_s = old_feedrate_mm_s;
    retracted[active_extruder] = retracting;

  } // retract()

#endif // FWRETRACT

#if ENABLED(MIXING_EXTRUDER)

  void normalize_mix() {
    float mix_total = 0.0;
    for (int i = 0; i < MIXING_STEPPERS; i++) {
      float v = mixing_factor[i];
      if (v < 0) v = mixing_factor[i] = 0;
      mix_total += v;
    }
    // Scale all values if they don't add up to ~1.0
    if (mix_total < 0.9999 || mix_total > 1.0001) {
      SERIAL_PROTOCOLLNPGM("Warning: Mix factors must add up to 1.0. Scaling.");
      float mix_scale = 1.0 / mix_total;
      for (int i = 0; i < MIXING_STEPPERS; i++)
        mixing_factor[i] *= mix_scale;
    }
  }

  #if ENABLED(DIRECT_MIXING_IN_G1)
    // Get mixing parameters from the GCode
    // Factors that are left out are set to 0
    // The total "must" be 1.0 (but it will be normalized)
    void gcode_get_mix() {
      const char* mixing_codes = "ABCDHI";
      for (int i = 0; i < MIXING_STEPPERS; i++)
        mixing_factor[i] = code_seen(mixing_codes[i]) ? code_value_float() : 0;

      normalize_mix();
    }
  #endif

#endif

/**
 * ***************************************************************************
 * ***************************** G-CODE HANDLING *****************************
 * ***************************************************************************
 */

/**
 * Set XYZE destination and feedrate from the current GCode command
 *
 *  - Set destination from included axis codes
 *  - Set to current for missing axis codes
 *  - Set the feedrate, if included
 */
void gcode_get_destination() {
  LOOP_XYZE(i) {
    if (code_seen(axis_codes[i]))
      destination[i] = code_value_axis_units(i) + (axis_relative_modes[i] || relative_mode ? current_position[i] : 0);
    else
      destination[i] = current_position[i];
  }

  if (code_seen('F') && code_value_linear_units() > 0.0)
    feedrate_mm_s = MMM_TO_MMS(code_value_linear_units());

  #if ENABLED(PRINTCOUNTER)
    if (!DEBUGGING(DRYRUN))
      print_job_timer.incFilamentUsed(destination[E_AXIS] - current_position[E_AXIS]);
  #endif

  // Get ABCDHI mixing factors
  #if ENABLED(MIXING_EXTRUDER) && ENABLED(DIRECT_MIXING_IN_G1)
    gcode_get_mix();
  #endif
}

void unknown_command_error() {
  SERIAL_ECHO_START;
  SERIAL_ECHOPAIR(MSG_UNKNOWN_COMMAND, current_command);
  SERIAL_ECHOLNPGM("\"");
}

#if ENABLED(HOST_KEEPALIVE_FEATURE)

  /**
   * Output a "busy" message at regular intervals
   * while the machine is not accepting commands.
   */
  void host_keepalive() {
    millis_t ms = millis();
    if (host_keepalive_interval && busy_state != NOT_BUSY) {
      if (PENDING(ms, next_busy_signal_ms)) return;
      switch (busy_state) {
        case IN_HANDLER:
        case IN_PROCESS:
          SERIAL_ECHO_START;
          SERIAL_ECHOLNPGM(MSG_BUSY_PROCESSING);
          break;
        case PAUSED_FOR_USER:
          SERIAL_ECHO_START;
          SERIAL_ECHOLNPGM(MSG_BUSY_PAUSED_FOR_USER);
          break;
        case PAUSED_FOR_INPUT:
          SERIAL_ECHO_START;
          SERIAL_ECHOLNPGM(MSG_BUSY_PAUSED_FOR_INPUT);
          break;
        default:
          break;
      }
    }
    next_busy_signal_ms = ms + host_keepalive_interval * 1000UL;
  }

#endif //HOST_KEEPALIVE_FEATURE

bool position_is_reachable(float target[XYZ]
  #if HAS_BED_PROBE
    , bool by_probe=false
  #endif
) {
  float dx = RAW_X_POSITION(target[X_AXIS]),
        dy = RAW_Y_POSITION(target[Y_AXIS]);

  #if HAS_BED_PROBE
    if (by_probe) {
      dx -= X_PROBE_OFFSET_FROM_EXTRUDER;
      dy -= Y_PROBE_OFFSET_FROM_EXTRUDER;
    }
  #endif

  #if IS_SCARA
    #if MIDDLE_DEAD_ZONE_R > 0
      const float R2 = HYPOT2(dx - SCARA_OFFSET_X, dy - SCARA_OFFSET_Y);
      return R2 >= sq(float(MIDDLE_DEAD_ZONE_R)) && R2 <= sq(L1 + L2);
    #else
      return HYPOT2(dx - SCARA_OFFSET_X, dy - SCARA_OFFSET_Y) <= sq(L1 + L2);
    #endif
  #elif ENABLED(DELTA)
    return HYPOT2(dx, dy) <= sq(DELTA_PRINTABLE_RADIUS);
  #else
    const float dz = RAW_Z_POSITION(target[Z_AXIS]);
    return dx >= X_MIN_POS - 0.0001 && dx <= X_MAX_POS + 0.0001
        && dy >= Y_MIN_POS - 0.0001 && dy <= Y_MAX_POS + 0.0001
        && dz >= Z_MIN_POS - 0.0001 && dz <= Z_MAX_POS + 0.0001;
  #endif
}

/**************************************************
 ***************** GCode Handlers *****************
 **************************************************/

/**
 * G0, G1: Coordinated movement of X Y Z E axes
 */
inline void gcode_G0_G1(
  #if IS_SCARA
    bool fast_move=false
  #endif
) {
  if (IsRunning()) {
    gcode_get_destination(); // For X Y Z E F

    #if ENABLED(FWRETRACT)

      if (autoretract_enabled && !(code_seen('X') || code_seen('Y') || code_seen('Z')) && code_seen('E')) {
        float echange = destination[E_AXIS] - current_position[E_AXIS];
        // Is this move an attempt to retract or recover?
        if ((echange < -MIN_RETRACT && !retracted[active_extruder]) || (echange > MIN_RETRACT && retracted[active_extruder])) {
          current_position[E_AXIS] = destination[E_AXIS]; // hide the slicer-generated retract/recover from calculations
          sync_plan_position_e();  // AND from the planner
          retract(!retracted[active_extruder]);
          return;
        }
      }

    #endif //FWRETRACT

    #if IS_SCARA
      fast_move ? prepare_uninterpolated_move_to_destination() : prepare_move_to_destination();
    #else
      prepare_move_to_destination();
    #endif
  }
}

/**
 * G2: Clockwise Arc
 * G3: Counterclockwise Arc
 *
 * This command has two forms: IJ-form and R-form.
 *
 *  - I specifies an X offset. J specifies a Y offset.
 *    At least one of the IJ parameters is required.
 *    X and Y can be omitted to do a complete circle.
 *    The given XY is not error-checked. The arc ends
 *     based on the angle of the destination.
 *    Mixing I or J with R will throw an error.
 *
 *  - R specifies the radius. X or Y is required.
 *    Omitting both X and Y will throw an error.
 *    X or Y must differ from the current XY.
 *    Mixing R with I or J will throw an error.
 *
 *  Examples:
 *
 *    G2 I10           ; CW circle centered at X+10
 *    G3 X20 Y12 R14   ; CCW circle with r=14 ending at X20 Y12
 */
#if ENABLED(ARC_SUPPORT)
  inline void gcode_G2_G3(bool clockwise) {
    if (IsRunning()) {

      #if ENABLED(SF_ARC_FIX)
        bool relative_mode_backup = relative_mode;
        relative_mode = true;
      #endif

      gcode_get_destination();

      #if ENABLED(SF_ARC_FIX)
        relative_mode = relative_mode_backup;
      #endif

      float arc_offset[2] = { 0.0, 0.0 };
      if (code_seen('R')) {
        const float r = code_value_axis_units(X_AXIS),
                    x1 = current_position[X_AXIS], y1 = current_position[Y_AXIS],
                    x2 = destination[X_AXIS], y2 = destination[Y_AXIS];
        if (r && (x2 != x1 || y2 != y1)) {
          const float e = clockwise ? -1 : 1,                     // clockwise -1, counterclockwise 1
                      dx = x2 - x1, dy = y2 - y1,                 // X and Y differences
                      d = HYPOT(dx, dy),                          // Linear distance between the points
                      h = sqrt(sq(r) - sq(d * 0.5)),              // Distance to the arc pivot-point
                      mx = (x1 + x2) * 0.5, my = (y1 + y2) * 0.5, // Point between the two points
                      sx = -dy / d, sy = dx / d,                  // Slope of the perpendicular bisector
                      cx = mx + e * h * sx, cy = my + e * h * sy; // Pivot-point of the arc
          arc_offset[X_AXIS] = cx - x1;
          arc_offset[Y_AXIS] = cy - y1;
        }
      }
      else {
        if (code_seen('I')) arc_offset[X_AXIS] = code_value_axis_units(X_AXIS);
        if (code_seen('J')) arc_offset[Y_AXIS] = code_value_axis_units(Y_AXIS);
      }

      if (arc_offset[0] || arc_offset[1]) {
        // Send an arc to the planner
        plan_arc(destination, arc_offset, clockwise);
        refresh_cmd_timeout();
      }
      else {
        // Bad arguments
        SERIAL_ERROR_START;
        SERIAL_ERRORLNPGM(MSG_ERR_ARC_ARGS);
      }
    }
  }
#endif

/**
 * G4: Dwell S<seconds> or P<milliseconds>
 */
inline void gcode_G4() {
  millis_t dwell_ms = 0;

  if (code_seen('P')) dwell_ms = code_value_millis(); // milliseconds to wait
  if (code_seen('S')) dwell_ms = code_value_millis_from_seconds(); // seconds to wait

  stepper.synchronize();
  refresh_cmd_timeout();
  dwell_ms += previous_cmd_ms;  // keep track of when we started waiting

  if (!lcd_hasstatus()) LCD_MESSAGEPGM(MSG_DWELL);

  while (PENDING(millis(), dwell_ms)) idle();
}

#if ENABLED(BEZIER_CURVE_SUPPORT)

  /**
   * Parameters interpreted according to:
   * http://linuxcnc.org/docs/2.6/html/gcode/gcode.html#sec:G5-Cubic-Spline
   * However I, J omission is not supported at this point; all
   * parameters can be omitted and default to zero.
   */

  /**
   * G5: Cubic B-spline
   */
  inline void gcode_G5() {
    if (IsRunning()) {

      gcode_get_destination();

      float offset[] = {
        code_seen('I') ? code_value_axis_units(X_AXIS) : 0.0,
        code_seen('J') ? code_value_axis_units(Y_AXIS) : 0.0,
        code_seen('P') ? code_value_axis_units(X_AXIS) : 0.0,
        code_seen('Q') ? code_value_axis_units(Y_AXIS) : 0.0
      };

      plan_cubic_move(offset);
    }
  }

#endif // BEZIER_CURVE_SUPPORT

#if ENABLED(FWRETRACT)

  /**
   * G10 - Retract filament according to settings of M207
   * G11 - Recover filament according to settings of M208
   */
  inline void gcode_G10_G11(bool doRetract=false) {
    #if EXTRUDERS > 1
      if (doRetract) {
        retracted_swap[active_extruder] = (code_seen('S') && code_value_bool()); // checks for swap retract argument
      }
    #endif
    retract(doRetract
     #if EXTRUDERS > 1
      , retracted_swap[active_extruder]
     #endif
    );
  }

#endif //FWRETRACT

#if ENABLED(NOZZLE_CLEAN_FEATURE)
  /**
   * G12: Clean the nozzle
   */
  inline void gcode_G12() {
    // Don't allow nozzle cleaning without homing first
    if (axis_unhomed_error(true, true, true)) { return; }

    uint8_t const pattern = code_seen('P') ? code_value_ushort() : 0;
    uint8_t const strokes = code_seen('S') ? code_value_ushort() : NOZZLE_CLEAN_STROKES;
    uint8_t const objects = code_seen('T') ? code_value_ushort() : 3;

    Nozzle::clean(pattern, strokes, objects);
  }
#endif

#if ENABLED(INCH_MODE_SUPPORT)
  /**
   * G20: Set input mode to inches
   */
  inline void gcode_G20() { set_input_linear_units(LINEARUNIT_INCH); }

  /**
   * G21: Set input mode to millimeters
   */
  inline void gcode_G21() { set_input_linear_units(LINEARUNIT_MM); }
#endif

#if ENABLED(NOZZLE_PARK_FEATURE)
  /**
   * G27: Park the nozzle
   */
  inline void gcode_G27() {
    // Don't allow nozzle parking without homing first
    if (axis_unhomed_error(true, true, true)) { return; }
    uint8_t const z_action = code_seen('P') ? code_value_ushort() : 0;
    Nozzle::park(z_action);
  }
#endif // NOZZLE_PARK_FEATURE

#if ENABLED(QUICK_HOME)

  static void quick_home_xy() {

    // Pretend the current position is 0,0
    current_position[X_AXIS] = current_position[Y_AXIS] = 0.0;
    sync_plan_position();

    int x_axis_home_dir =
      #if ENABLED(DUAL_X_CARRIAGE)
        x_home_dir(active_extruder)
      #else
        home_dir(X_AXIS)
      #endif
    ;

    float mlx = max_length(X_AXIS),
          mly = max_length(Y_AXIS),
          mlratio = mlx > mly ? mly / mlx : mlx / mly,
          fr_mm_s = min(homing_feedrate_mm_s[X_AXIS], homing_feedrate_mm_s[Y_AXIS]) * sqrt(sq(mlratio) + 1.0);

    do_blocking_move_to_xy(1.5 * mlx * x_axis_home_dir, 1.5 * mly * home_dir(Y_AXIS), fr_mm_s);
    endstops.hit_on_purpose(); // clear endstop hit flags
    current_position[X_AXIS] = current_position[Y_AXIS] = 0.0;

  }

#endif // QUICK_HOME

#if ENABLED(DEBUG_LEVELING_FEATURE)

  void log_machine_info() {
    SERIAL_ECHOPGM("Machine Type: ");
    #if ENABLED(DELTA)
      SERIAL_ECHOLNPGM("Delta");
    #elif IS_SCARA
      SERIAL_ECHOLNPGM("SCARA");
    #elif ENABLED(COREXY) || ENABLED(COREXZ) || ENABLED(COREYZ)
      SERIAL_ECHOLNPGM("Core");
    #else
      SERIAL_ECHOLNPGM("Cartesian");
    #endif

    SERIAL_ECHOPGM("Probe: ");
    #if ENABLED(FIX_MOUNTED_PROBE)
      SERIAL_ECHOLNPGM("FIX_MOUNTED_PROBE");
    #elif ENABLED(BLTOUCH)
      SERIAL_ECHOLNPGM("BLTOUCH");
    #elif HAS_Z_SERVO_ENDSTOP
      SERIAL_ECHOLNPGM("SERVO PROBE");
    #elif ENABLED(Z_PROBE_SLED)
      SERIAL_ECHOLNPGM("Z_PROBE_SLED");
    #elif ENABLED(Z_PROBE_ALLEN_KEY)
      SERIAL_ECHOLNPGM("Z_PROBE_ALLEN_KEY");
    #else
      SERIAL_ECHOLNPGM("NONE");
    #endif

    #if HAS_BED_PROBE
      SERIAL_ECHOPAIR("Probe Offset X:", X_PROBE_OFFSET_FROM_EXTRUDER);
      SERIAL_ECHOPAIR(" Y:", Y_PROBE_OFFSET_FROM_EXTRUDER);
      SERIAL_ECHOPAIR(" Z:", zprobe_zoffset);
      #if (X_PROBE_OFFSET_FROM_EXTRUDER > 0)
        SERIAL_ECHOPGM(" (Right");
      #elif (X_PROBE_OFFSET_FROM_EXTRUDER < 0)
        SERIAL_ECHOPGM(" (Left");
      #elif (Y_PROBE_OFFSET_FROM_EXTRUDER != 0)
        SERIAL_ECHOPGM(" (Middle");
      #else
        SERIAL_ECHOPGM(" (Aligned With");
      #endif
      #if (Y_PROBE_OFFSET_FROM_EXTRUDER > 0)
        SERIAL_ECHOPGM("-Back");
      #elif (Y_PROBE_OFFSET_FROM_EXTRUDER < 0)
        SERIAL_ECHOPGM("-Front");
      #elif (X_PROBE_OFFSET_FROM_EXTRUDER != 0)
        SERIAL_ECHOPGM("-Center");
      #endif
      if (zprobe_zoffset < 0)
        SERIAL_ECHOPGM(" & Below");
      else if (zprobe_zoffset > 0)
        SERIAL_ECHOPGM(" & Above");
      else
        SERIAL_ECHOPGM(" & Same Z as");
      SERIAL_ECHOLNPGM(" Nozzle)");
    #endif

    #if HAS_ABL
      SERIAL_ECHOPGM("Auto Bed Leveling: ");
      #if ENABLED(AUTO_BED_LEVELING_LINEAR)
        SERIAL_ECHOPGM("LINEAR");
      #elif ENABLED(AUTO_BED_LEVELING_BILINEAR)
        SERIAL_ECHOPGM("BILINEAR");
      #elif ENABLED(AUTO_BED_LEVELING_3POINT)
        SERIAL_ECHOPGM("3POINT");
      #endif
      if (planner.abl_enabled) {
        SERIAL_ECHOLNPGM(" (enabled)");
        #if ENABLED(AUTO_BED_LEVELING_LINEAR) || ENABLED(AUTO_BED_LEVELING_3POINT)
          float diff[XYZ] = {
            stepper.get_axis_position_mm(X_AXIS) - current_position[X_AXIS],
            stepper.get_axis_position_mm(Y_AXIS) - current_position[Y_AXIS],
            stepper.get_axis_position_mm(Z_AXIS) - current_position[Z_AXIS]
          };
          SERIAL_ECHOPGM("ABL Adjustment X");
          if (diff[X_AXIS] > 0) SERIAL_CHAR('+');
          SERIAL_ECHO(diff[X_AXIS]);
          SERIAL_ECHOPGM(" Y");
          if (diff[Y_AXIS] > 0) SERIAL_CHAR('+');
          SERIAL_ECHO(diff[Y_AXIS]);
          SERIAL_ECHOPGM(" Z");
          if (diff[Z_AXIS] > 0) SERIAL_CHAR('+');
          SERIAL_ECHO(diff[Z_AXIS]);
        #elif ENABLED(AUTO_BED_LEVELING_BILINEAR)
          SERIAL_ECHOPAIR("ABL Adjustment Z", bilinear_z_offset(current_position));
        #endif
      }
      SERIAL_EOL;
    #elif ENABLED(MESH_BED_LEVELING)
      SERIAL_ECHOPGM("Mesh Bed Leveling");
      if (mbl.active()) {
        SERIAL_ECHOLNPGM(" (enabled)");
        SERIAL_ECHOPAIR("MBL Adjustment Z", mbl.get_z(RAW_CURRENT_POSITION(X_AXIS), RAW_CURRENT_POSITION(Y_AXIS)));
      }
      SERIAL_EOL;
    #endif

  }

#endif // DEBUG_LEVELING_FEATURE

#if ENABLED(DELTA)

  /**
   * A delta can only safely home all axes at the same time
   * This is like quick_home_xy() but for 3 towers.
   */
  inline void home_delta() {
    // Init the current position of all carriages to 0,0,0
    memset(current_position, 0, sizeof(current_position));
    sync_plan_position();

    // Move all carriages together linearly until an endstop is hit.
    current_position[X_AXIS] = current_position[Y_AXIS] = current_position[Z_AXIS] = (Z_MAX_LENGTH + 10);
    feedrate_mm_s = homing_feedrate_mm_s[X_AXIS];
    line_to_current_position();
    stepper.synchronize();
    endstops.hit_on_purpose(); // clear endstop hit flags

    // Probably not needed. Double-check this line:
    memset(current_position, 0, sizeof(current_position));

    // At least one carriage has reached the top.
    // Now back off and re-home each carriage separately.
    HOMEAXIS(A);
    HOMEAXIS(B);
    HOMEAXIS(C);

    // Set all carriages to their home positions
    // Do this here all at once for Delta, because
    // XYZ isn't ABC. Applying this per-tower would
    // give the impression that they are the same.
    LOOP_XYZ(i) set_axis_is_at_home((AxisEnum)i);

    SYNC_PLAN_POSITION_KINEMATIC();

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("(DELTA)", current_position);
    #endif
  }

#endif // DELTA

#if ENABLED(Z_SAFE_HOMING)

  inline void home_z_safely() {

    // Disallow Z homing if X or Y are unknown
    if (!axis_known_position[X_AXIS] || !axis_known_position[Y_AXIS]) {
      LCD_MESSAGEPGM(MSG_ERR_Z_HOMING);
      SERIAL_ECHO_START;
      SERIAL_ECHOLNPGM(MSG_ERR_Z_HOMING);
      return;
    }

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("Z_SAFE_HOMING >>>");
    #endif

    SYNC_PLAN_POSITION_KINEMATIC();

    /**
     * Move the Z probe (or just the nozzle) to the safe homing point
     */
    destination[X_AXIS] = LOGICAL_X_POSITION(Z_SAFE_HOMING_X_POINT);
    destination[Y_AXIS] = LOGICAL_Y_POSITION(Z_SAFE_HOMING_Y_POINT);
    destination[Z_AXIS] = current_position[Z_AXIS]; // Z is already at the right height

    if (position_is_reachable(
          destination
          #if HOMING_Z_WITH_PROBE
            , true
          #endif
        )
    ) {
      #if HOMING_Z_WITH_PROBE
        destination[X_AXIS] -= X_PROBE_OFFSET_FROM_EXTRUDER;
        destination[Y_AXIS] -= Y_PROBE_OFFSET_FROM_EXTRUDER;
      #endif
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) DEBUG_POS("Z_SAFE_HOMING", destination);
      #endif
      do_blocking_move_to_xy(destination[X_AXIS], destination[Y_AXIS]);
      HOMEAXIS(Z);
    }
    else {
      LCD_MESSAGEPGM(MSG_ZPROBE_OUT);
      SERIAL_ECHO_START;
      SERIAL_ECHOLNPGM(MSG_ZPROBE_OUT);
    }

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("<<< Z_SAFE_HOMING");
    #endif
  }

#endif // Z_SAFE_HOMING

/**
 * G28: Home all axes according to settings
 *
 * Parameters
 *
 *  None  Home to all axes with no parameters.
 *        With QUICK_HOME enabled XY will home together, then Z.
 *
 * Cartesian parameters
 *
 *  X   Home to the X endstop
 *  Y   Home to the Y endstop
 *  Z   Home to the Z endstop
 *
 */
inline void gcode_G28() {

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOLNPGM(">>> gcode_G28");
      log_machine_info();
    }
  #endif

  // Wait for planner moves to finish!
  stepper.synchronize();

  // For auto bed leveling, clear the level matrix
  #if HAS_ABL
    reset_bed_level();
  #endif

  // Always home with tool 0 active
  #if HOTENDS > 1
    uint8_t old_tool_index = active_extruder;
    tool_change(0, 0, true);
  #endif

  #if ENABLED(DUAL_X_CARRIAGE) || ENABLED(DUAL_NOZZLE_DUPLICATION_MODE)
    extruder_duplication_enabled = false;
  #endif

  /**
   * For mesh bed leveling deactivate the mesh calculations, will be turned
   * on again when homing all axis
   */
  #if ENABLED(MESH_BED_LEVELING)
    float pre_home_z = MESH_HOME_SEARCH_Z;
    if (mbl.active()) {
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("MBL was active");
      #endif
      // Save known Z position if already homed
      if (axis_homed[X_AXIS] && axis_homed[Y_AXIS] && axis_homed[Z_AXIS]) {
        pre_home_z = current_position[Z_AXIS];
        pre_home_z += mbl.get_z(RAW_CURRENT_POSITION(X_AXIS), RAW_CURRENT_POSITION(Y_AXIS));
      }
      mbl.set_active(false);
      current_position[Z_AXIS] = pre_home_z;
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) DEBUG_POS("Set Z to pre_home_z", current_position);
      #endif
    }
  #endif

  setup_for_endstop_or_probe_move();
  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("> endstops.enable(true)");
  #endif
  endstops.enable(true); // Enable endstops for next homing move

  #if ENABLED(DELTA)

    home_delta();

  #else // NOT DELTA

    bool homeX = code_seen('X'), homeY = code_seen('Y'), homeZ = code_seen('Z');

    home_all_axis = (!homeX && !homeY && !homeZ) || (homeX && homeY && homeZ);

    set_destination_to_current();

    #if Z_HOME_DIR > 0  // If homing away from BED do Z first

      if (home_all_axis || homeZ) {
        HOMEAXIS(Z);
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("> HOMEAXIS(Z)", current_position);
        #endif
      }

    #else

      if (home_all_axis || homeX || homeY) {
        // Raise Z before homing any other axes and z is not already high enough (never lower z)
        destination[Z_AXIS] = LOGICAL_Z_POSITION(Z_HOMING_HEIGHT);
        if (destination[Z_AXIS] > current_position[Z_AXIS]) {

          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING))
              SERIAL_ECHOLNPAIR("Raise Z (before homing) to ", destination[Z_AXIS]);
          #endif

          do_blocking_move_to_z(destination[Z_AXIS]);
        }
      }

    #endif

    #if ENABLED(QUICK_HOME)

      if (home_all_axis || (homeX && homeY)) quick_home_xy();

    #endif

    #if ENABLED(HOME_Y_BEFORE_X)

      // Home Y
      if (home_all_axis || homeY) {
        HOMEAXIS(Y);
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("> homeY", current_position);
        #endif
      }

    #endif

    // Home X
    if (home_all_axis || homeX) {
      #if ENABLED(DUAL_X_CARRIAGE)
        int tmp_extruder = active_extruder;
        active_extruder = !active_extruder;
        HOMEAXIS(X);
        inactive_extruder_x_pos = RAW_X_POSITION(current_position[X_AXIS]);
        active_extruder = tmp_extruder;
        HOMEAXIS(X);
        // reset state used by the different modes
        memcpy(raised_parked_position, current_position, sizeof(raised_parked_position));
        delayed_move_time = 0;
        active_extruder_parked = true;
      #else
        HOMEAXIS(X);
      #endif
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) DEBUG_POS("> homeX", current_position);
      #endif
    }

    #if DISABLED(HOME_Y_BEFORE_X)
      // Home Y
      if (home_all_axis || homeY) {
        HOMEAXIS(Y);
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("> homeY", current_position);
        #endif
      }
    #endif

    // Home Z last if homing towards the bed
    #if Z_HOME_DIR < 0
      if (home_all_axis || homeZ) {
        #if ENABLED(Z_SAFE_HOMING)
          home_z_safely();
        #else
          HOMEAXIS(Z);
        #endif
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("> (home_all_axis || homeZ) > final", current_position);
        #endif
      } // home_all_axis || homeZ
    #endif // Z_HOME_DIR < 0

    SYNC_PLAN_POSITION_KINEMATIC();

  #endif // !DELTA (gcode_G28)

  endstops.not_homing();

  // Enable mesh leveling again
  #if ENABLED(MESH_BED_LEVELING)
    if (mbl.has_mesh()) {
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("MBL has mesh");
      #endif
      if (home_all_axis || (axis_homed[X_AXIS] && axis_homed[Y_AXIS] && homeZ)) {
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("MBL Z homing");
        #endif
        current_position[Z_AXIS] = MESH_HOME_SEARCH_Z
          #if Z_HOME_DIR > 0
            + Z_MAX_POS
          #endif
        ;
        SYNC_PLAN_POSITION_KINEMATIC();
        mbl.set_active(true);
        #if ENABLED(MESH_G28_REST_ORIGIN)
          current_position[Z_AXIS] = 0.0;
          set_destination_to_current();
          line_to_destination(homing_feedrate_mm_s[Z_AXIS]);
          stepper.synchronize();
          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) DEBUG_POS("MBL Rest Origin", current_position);
          #endif
        #else
          planner.unapply_leveling(current_position);
          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) DEBUG_POS("MBL adjusted MESH_HOME_SEARCH_Z", current_position);
          #endif
        #endif
      }
      else if ((axis_homed[X_AXIS] && axis_homed[Y_AXIS] && axis_homed[Z_AXIS]) && (homeX || homeY)) {
        current_position[Z_AXIS] = pre_home_z;
        SYNC_PLAN_POSITION_KINEMATIC();
        mbl.set_active(true);
        planner.unapply_leveling(current_position);
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("MBL Home X or Y", current_position);
        #endif
      }
    }
  #endif

  #if ENABLED(DELTA)
    // move to a height where we can use the full xy-area
    do_blocking_move_to_z(delta_clip_start_height);
  #endif

  clean_up_after_endstop_or_probe_move();

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("<<< gcode_G28");
  #endif

  // Restore the active tool after homing
  #if HOTENDS > 1
    tool_change(old_tool_index, 0, true);
  #endif

  report_current_position();
}

#if HAS_PROBING_PROCEDURE

  void out_of_range_error(const char* p_edge) {
    SERIAL_PROTOCOLPGM("?Probe ");
    serialprintPGM(p_edge);
    SERIAL_PROTOCOLLNPGM(" position out of range.");
  }

#endif

#if ENABLED(MESH_BED_LEVELING)

  inline void _mbl_goto_xy(float x, float y) {
    float old_feedrate_mm_s = feedrate_mm_s;
    feedrate_mm_s = homing_feedrate_mm_s[X_AXIS];

    current_position[Z_AXIS] = MESH_HOME_SEARCH_Z
      #if Z_CLEARANCE_BETWEEN_PROBES > Z_HOMING_HEIGHT
        + Z_CLEARANCE_BETWEEN_PROBES
      #elif Z_HOMING_HEIGHT > 0
        + Z_HOMING_HEIGHT
      #endif
    ;
    line_to_current_position();

    current_position[X_AXIS] = LOGICAL_X_POSITION(x);
    current_position[Y_AXIS] = LOGICAL_Y_POSITION(y);
    line_to_current_position();

    #if Z_CLEARANCE_BETWEEN_PROBES > 0 || Z_HOMING_HEIGHT > 0
      current_position[Z_AXIS] = LOGICAL_Z_POSITION(MESH_HOME_SEARCH_Z);
      line_to_current_position();
    #endif

    feedrate_mm_s = old_feedrate_mm_s;
    stepper.synchronize();
  }

  /**
   * G29: Mesh-based Z probe, probes a grid and produces a
   *      mesh to compensate for variable bed height
   *
   * Parameters With MESH_BED_LEVELING:
   *
   *  S0              Produce a mesh report
   *  S1              Start probing mesh points
   *  S2              Probe the next mesh point
   *  S3 Xn Yn Zn.nn  Manually modify a single point
   *  S4 Zn.nn        Set z offset. Positive away from bed, negative closer to bed.
   *  S5              Reset and disable mesh
   *
   * The S0 report the points as below
   *
   *  +----> X-axis  1-n
   *  |
   *  |
   *  v Y-axis  1-n
   *
   */
  inline void gcode_G29() {

    static int probe_point = -1;
    MeshLevelingState state = code_seen('S') ? (MeshLevelingState)code_value_byte() : MeshReport;
    if (state < 0 || state > 5) {
      SERIAL_PROTOCOLLNPGM("S out of range (0-5).");
      return;
    }

    int8_t px, py;

    switch (state) {
      case MeshReport:
        if (mbl.has_mesh()) {
          SERIAL_PROTOCOLPAIR("State: ", mbl.active() ? MSG_ON : MSG_OFF);
          SERIAL_PROTOCOLLNPGM("\nNum X,Y: " STRINGIFY(MESH_NUM_X_POINTS) "," STRINGIFY(MESH_NUM_Y_POINTS));
          SERIAL_PROTOCOLLNPGM("Z search height: " STRINGIFY(MESH_HOME_SEARCH_Z));
          SERIAL_PROTOCOLPGM("Z offset: "); SERIAL_PROTOCOL_F(mbl.z_offset, 5);
          SERIAL_PROTOCOLLNPGM("\nMeasured points:");
          for (py = 0; py < MESH_NUM_Y_POINTS; py++) {
            for (px = 0; px < MESH_NUM_X_POINTS; px++) {
              SERIAL_PROTOCOLPGM("  ");
              SERIAL_PROTOCOL_F(mbl.z_values[py][px], 5);
            }
            SERIAL_EOL;
          }
        }
        else
          SERIAL_PROTOCOLLNPGM("Mesh bed leveling not active.");
        break;

      case MeshStart:
        mbl.reset();
        probe_point = 0;
        enqueue_and_echo_commands_P(PSTR("G28\nG29 S2"));
        break;

      case MeshNext:
        if (probe_point < 0) {
          SERIAL_PROTOCOLLNPGM("Start mesh probing with \"G29 S1\" first.");
          return;
        }
        // For each G29 S2...
        if (probe_point == 0) {
          // For the initial G29 S2 make Z a positive value (e.g., 4.0)
          current_position[Z_AXIS] = MESH_HOME_SEARCH_Z
            #if Z_HOME_DIR > 0
              + Z_MAX_POS
            #endif
          ;
          SYNC_PLAN_POSITION_KINEMATIC();
        }
        else {
          // For G29 S2 after adjusting Z.
          mbl.set_zigzag_z(probe_point - 1, current_position[Z_AXIS]);
        }
        // If there's another point to sample, move there with optional lift.
        if (probe_point < (MESH_NUM_X_POINTS) * (MESH_NUM_Y_POINTS)) {
          mbl.zigzag(probe_point, px, py);
          _mbl_goto_xy(mbl.get_probe_x(px), mbl.get_probe_y(py));
          probe_point++;
        }
        else {
          // One last "return to the bed" (as originally coded) at completion
          current_position[Z_AXIS] = MESH_HOME_SEARCH_Z
            #if Z_CLEARANCE_BETWEEN_PROBES > Z_HOMING_HEIGHT
              + Z_CLEARANCE_BETWEEN_PROBES
            #elif Z_HOMING_HEIGHT > 0
              + Z_HOMING_HEIGHT
            #endif
          ;
          line_to_current_position();
          stepper.synchronize();

          // After recording the last point, activate the mbl and home
          SERIAL_PROTOCOLLNPGM("Mesh probing done.");
          probe_point = -1;
          mbl.set_has_mesh(true);
          enqueue_and_echo_commands_P(PSTR("G28"));
        }
        break;

      case MeshSet:
        if (code_seen('X')) {
          px = code_value_int() - 1;
          if (px < 0 || px >= MESH_NUM_X_POINTS) {
            SERIAL_PROTOCOLLNPGM("X out of range (1-" STRINGIFY(MESH_NUM_X_POINTS) ").");
            return;
          }
        }
        else {
          SERIAL_PROTOCOLLNPGM("X not entered.");
          return;
        }
        if (code_seen('Y')) {
          py = code_value_int() - 1;
          if (py < 0 || py >= MESH_NUM_Y_POINTS) {
            SERIAL_PROTOCOLLNPGM("Y out of range (1-" STRINGIFY(MESH_NUM_Y_POINTS) ").");
            return;
          }
        }
        else {
          SERIAL_PROTOCOLLNPGM("Y not entered.");
          return;
        }
        if (code_seen('Z')) {
          mbl.z_values[py][px] = code_value_axis_units(Z_AXIS);
        }
        else {
          SERIAL_PROTOCOLLNPGM("Z not entered.");
          return;
        }
        break;

      case MeshSetZOffset:
        if (code_seen('Z')) {
          mbl.z_offset = code_value_axis_units(Z_AXIS);
        }
        else {
          SERIAL_PROTOCOLLNPGM("Z not entered.");
          return;
        }
        break;

      case MeshReset:
        if (mbl.active()) {
          current_position[Z_AXIS] +=
            mbl.get_z(RAW_CURRENT_POSITION(X_AXIS), RAW_CURRENT_POSITION(Y_AXIS)) - MESH_HOME_SEARCH_Z;
          mbl.reset();
          SYNC_PLAN_POSITION_KINEMATIC();
        }
        else
          mbl.reset();

    } // switch(state)

    report_current_position();
  }

#elif HAS_ABL

  /**
   * G29: Detailed Z probe, probes the bed at 3 or more points.
   *      Will fail if the printer has not been homed with G28.
   *
   * Enhanced G29 Auto Bed Leveling Probe Routine
   *
   * Parameters With ABL_GRID:
   *
   *  P  Set the size of the grid that will be probed (P x P points).
   *     Not supported by non-linear delta printer bed leveling.
   *     Example: "G29 P4"
   *
   *  S  Set the XY travel speed between probe points (in units/min)
   *
   *  D  Dry-Run mode. Just evaluate the bed Topology - Don't apply
   *     or clean the rotation Matrix. Useful to check the topology
   *     after a first run of G29.
   *
   *  V  Set the verbose level (0-4). Example: "G29 V3"
   *
   *  T  Generate a Bed Topology Report. Example: "G29 P5 T" for a detailed report.
   *     This is useful for manual bed leveling and finding flaws in the bed (to
   *     assist with part placement).
   *     Not supported by non-linear delta printer bed leveling.
   *
   *  F  Set the Front limit of the probing grid
   *  B  Set the Back limit of the probing grid
   *  L  Set the Left limit of the probing grid
   *  R  Set the Right limit of the probing grid
   *
   * Global Parameters:
   *
   * E/e By default G29 will engage the Z probe, test the bed, then disengage.
   *     Include "E" to engage/disengage the Z probe for each sample.
   *     There's no extra effect if you have a fixed Z probe.
   *     Usage: "G29 E" or "G29 e"
   *
   */
  inline void gcode_G29() {

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      bool query = code_seen('Q');
      uint8_t old_debug_flags = marlin_debug_flags;
      if (query) marlin_debug_flags |= DEBUG_LEVELING;
      if (DEBUGGING(LEVELING)) {
        DEBUG_POS(">>> gcode_G29", current_position);
        log_machine_info();
      }
      marlin_debug_flags = old_debug_flags;
      if (query) return;
    #endif

    // Don't allow auto-leveling without homing first
    if (axis_unhomed_error(true, true, true)) return;

    int verbose_level = code_seen('V') ? code_value_int() : 1;
    if (verbose_level < 0 || verbose_level > 4) {
      SERIAL_PROTOCOLLNPGM("?(V)erbose Level is implausible (0-4).");
      return;
    }

    bool dryrun = code_seen('D'),
         stow_probe_after_each = code_seen('E');

    #if ABL_GRID

      if (verbose_level > 0) {
        SERIAL_PROTOCOLLNPGM("G29 Auto Bed Leveling");
        if (dryrun) SERIAL_PROTOCOLLNPGM("Running in DRY-RUN mode");
      }

      #if ABL_PLANAR

        bool do_topography_map = verbose_level > 2 || code_seen('T');

        // X and Y specify points in each direction, overriding the default
        // These values may be saved with the completed mesh
        int abl_grid_points_x = code_seen('X') ? code_value_int() : ABL_GRID_POINTS_X,
            abl_grid_points_y = code_seen('Y') ? code_value_int() : ABL_GRID_POINTS_Y;

        if (code_seen('P')) abl_grid_points_x = abl_grid_points_y = code_value_int();

        if (abl_grid_points_x < 2 || abl_grid_points_y < 2) {
          SERIAL_PROTOCOLLNPGM("?Number of probe points is implausible (2 minimum).");
          return;
        }

      #else

         const int abl_grid_points_x = ABL_GRID_POINTS_X, abl_grid_points_y = ABL_GRID_POINTS_Y;

      #endif

      xy_probe_feedrate_mm_s = MMM_TO_MMS(code_seen('S') ? code_value_linear_units() : XY_PROBE_SPEED);

      int left_probe_bed_position = code_seen('L') ? (int)code_value_axis_units(X_AXIS) : LOGICAL_X_POSITION(LEFT_PROBE_BED_POSITION),
          right_probe_bed_position = code_seen('R') ? (int)code_value_axis_units(X_AXIS) : LOGICAL_X_POSITION(RIGHT_PROBE_BED_POSITION),
          front_probe_bed_position = code_seen('F') ? (int)code_value_axis_units(Y_AXIS) : LOGICAL_Y_POSITION(FRONT_PROBE_BED_POSITION),
          back_probe_bed_position = code_seen('B') ? (int)code_value_axis_units(Y_AXIS) : LOGICAL_Y_POSITION(BACK_PROBE_BED_POSITION);

      bool left_out_l = left_probe_bed_position < LOGICAL_X_POSITION(MIN_PROBE_X),
           left_out = left_out_l || left_probe_bed_position > right_probe_bed_position - (MIN_PROBE_EDGE),
           right_out_r = right_probe_bed_position > LOGICAL_X_POSITION(MAX_PROBE_X),
           right_out = right_out_r || right_probe_bed_position < left_probe_bed_position + MIN_PROBE_EDGE,
           front_out_f = front_probe_bed_position < LOGICAL_Y_POSITION(MIN_PROBE_Y),
           front_out = front_out_f || front_probe_bed_position > back_probe_bed_position - (MIN_PROBE_EDGE),
           back_out_b = back_probe_bed_position > LOGICAL_Y_POSITION(MAX_PROBE_Y),
           back_out = back_out_b || back_probe_bed_position < front_probe_bed_position + MIN_PROBE_EDGE;

      if (left_out || right_out || front_out || back_out) {
        if (left_out) {
          out_of_range_error(PSTR("(L)eft"));
          left_probe_bed_position = left_out_l ? LOGICAL_X_POSITION(MIN_PROBE_X) : right_probe_bed_position - (MIN_PROBE_EDGE);
        }
        if (right_out) {
          out_of_range_error(PSTR("(R)ight"));
          right_probe_bed_position = right_out_r ? LOGICAL_Y_POSITION(MAX_PROBE_X) : left_probe_bed_position + MIN_PROBE_EDGE;
        }
        if (front_out) {
          out_of_range_error(PSTR("(F)ront"));
          front_probe_bed_position = front_out_f ? LOGICAL_Y_POSITION(MIN_PROBE_Y) : back_probe_bed_position - (MIN_PROBE_EDGE);
        }
        if (back_out) {
          out_of_range_error(PSTR("(B)ack"));
          back_probe_bed_position = back_out_b ? LOGICAL_Y_POSITION(MAX_PROBE_Y) : front_probe_bed_position + MIN_PROBE_EDGE;
        }
        return;
      }

    #endif // ABL_GRID

    stepper.synchronize();

    // Disable auto bed leveling during G29
    bool abl_should_enable = planner.abl_enabled;

    planner.abl_enabled = false;

    if (!dryrun) {
      // Re-orient the current position without leveling
      // based on where the steppers are positioned.
      set_current_from_steppers_for_axis(ALL_AXES);

      // Sync the planner to where the steppers stopped
      planner.sync_from_steppers();
    }

    setup_for_endstop_or_probe_move();

    // Deploy the probe. Probe will raise if needed.
    if (DEPLOY_PROBE()) {
      planner.abl_enabled = abl_should_enable;
      return;
    }

    float xProbe = 0, yProbe = 0, measured_z = 0;

    #if ABL_GRID

      // probe at the points of a lattice grid
      const float xGridSpacing = (right_probe_bed_position - left_probe_bed_position) / (abl_grid_points_x - 1),
                  yGridSpacing = (back_probe_bed_position - front_probe_bed_position) / (abl_grid_points_y - 1);

      #if ENABLED(AUTO_BED_LEVELING_BILINEAR)

        float zoffset = zprobe_zoffset;
        if (code_seen('Z')) zoffset += code_value_axis_units(Z_AXIS);

        if ( xGridSpacing != bilinear_grid_spacing[X_AXIS]
          || yGridSpacing != bilinear_grid_spacing[Y_AXIS]
          || left_probe_bed_position != bilinear_start[X_AXIS]
          || front_probe_bed_position != bilinear_start[Y_AXIS]
        ) {
          bilinear_grid_spacing[X_AXIS] = xGridSpacing;
          bilinear_grid_spacing[Y_AXIS] = yGridSpacing;
          bilinear_start[X_AXIS] = RAW_X_POSITION(left_probe_bed_position);
          bilinear_start[Y_AXIS] = RAW_Y_POSITION(front_probe_bed_position);
          // Can't re-enable (on error) until the new grid is written
          abl_should_enable = false;
        }

      #elif ENABLED(AUTO_BED_LEVELING_LINEAR)

        /**
         * solve the plane equation ax + by + d = z
         * A is the matrix with rows [x y 1] for all the probed points
         * B is the vector of the Z positions
         * the normal vector to the plane is formed by the coefficients of the
         * plane equation in the standard form, which is Vx*x+Vy*y+Vz*z+d = 0
         * so Vx = -a Vy = -b Vz = 1 (we want the vector facing towards positive Z
         */

        int abl2 = abl_grid_points_x * abl_grid_points_y,
            indexIntoAB[abl_grid_points_x][abl_grid_points_y],
            probePointCounter = -1;

        float eqnAMatrix[abl2 * 3], // "A" matrix of the linear system of equations
              eqnBVector[abl2],     // "B" vector of Z points
              mean = 0.0;

      #endif // AUTO_BED_LEVELING_LINEAR

      #if ENABLED(PROBE_Y_FIRST)
        #define PR_OUTER_VAR xCount
        #define PR_OUTER_END abl_grid_points_x
        #define PR_INNER_VAR yCount
        #define PR_INNER_END abl_grid_points_y
      #else
        #define PR_OUTER_VAR yCount
        #define PR_OUTER_END abl_grid_points_y
        #define PR_INNER_VAR xCount
        #define PR_INNER_END abl_grid_points_x
      #endif

      #if ENABLED(MAKERARM_SCARA)
        bool zig = true;
      #else
        bool zig = PR_OUTER_END & 1; //always end at [RIGHT_PROBE_BED_POSITION, BACK_PROBE_BED_POSITION]
      #endif

      for (uint8_t PR_OUTER_VAR = 0; PR_OUTER_VAR < PR_OUTER_END; PR_OUTER_VAR++) {

        int8_t inStart, inStop, inInc;

        if (zig) {
          inStart = 0;
          inStop = PR_INNER_END;
          inInc = 1;
        }
        else {
          inStart = PR_INNER_END - 1;
          inStop = -1;
          inInc = -1;
        }

        zig = !zig;

        for (int8_t PR_INNER_VAR = inStart; PR_INNER_VAR != inStop; PR_INNER_VAR += inInc) {

          float xBase = left_probe_bed_position + xGridSpacing * xCount,
                yBase = front_probe_bed_position + yGridSpacing * yCount;

          xProbe = floor(xBase + (xBase < 0 ? 0 : 0.5));
          yProbe = floor(yBase + (yBase < 0 ? 0 : 0.5));

          #if ENABLED(AUTO_BED_LEVELING_LINEAR)
            indexIntoAB[xCount][yCount] = ++probePointCounter;
          #endif

          #if IS_KINEMATIC
            // Avoid probing outside the round or hexagonal area
            float pos[XYZ] = { xProbe, yProbe, 0 };
            if (!position_is_reachable(pos, true)) continue;
          #endif

          measured_z = probe_pt(xProbe, yProbe, stow_probe_after_each, verbose_level);

          if (measured_z == NAN) {
            planner.abl_enabled = abl_should_enable;
            return;
          }

          #if ENABLED(AUTO_BED_LEVELING_LINEAR)

            mean += measured_z;
            eqnBVector[probePointCounter] = measured_z;
            eqnAMatrix[probePointCounter + 0 * abl2] = xProbe;
            eqnAMatrix[probePointCounter + 1 * abl2] = yProbe;
            eqnAMatrix[probePointCounter + 2 * abl2] = 1;

          #elif ENABLED(AUTO_BED_LEVELING_BILINEAR)

            bed_level_grid[xCount][yCount] = measured_z + zoffset;

          #endif

          idle();

        } //xProbe
      } //yProbe

    #elif ENABLED(AUTO_BED_LEVELING_3POINT)

      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("> 3-point Leveling");
      #endif

      // Probe at 3 arbitrary points
      vector_3 points[3] = {
        vector_3(ABL_PROBE_PT_1_X, ABL_PROBE_PT_1_Y, 0),
        vector_3(ABL_PROBE_PT_2_X, ABL_PROBE_PT_2_Y, 0),
        vector_3(ABL_PROBE_PT_3_X, ABL_PROBE_PT_3_Y, 0)
      };

      for (uint8_t i = 0; i < 3; ++i) {
        // Retain the last probe position
        xProbe = LOGICAL_X_POSITION(points[i].x);
        yProbe = LOGICAL_Y_POSITION(points[i].y);
        measured_z = points[i].z = probe_pt(xProbe, yProbe, stow_probe_after_each, verbose_level);
      }

      if (measured_z == NAN) {
        planner.abl_enabled = abl_should_enable;
        return;
      }

      if (!dryrun) {
        vector_3 planeNormal = vector_3::cross(points[0] - points[1], points[2] - points[1]).get_normal();
        if (planeNormal.z < 0) {
          planeNormal.x *= -1;
          planeNormal.y *= -1;
          planeNormal.z *= -1;
        }
        planner.bed_level_matrix = matrix_3x3::create_look_at(planeNormal);

        // Can't re-enable (on error) until the new grid is written
        abl_should_enable = false;
      }

    #endif // AUTO_BED_LEVELING_3POINT

    // Raise to _Z_CLEARANCE_DEPLOY_PROBE. Stow the probe.
    if (STOW_PROBE()) {
      planner.abl_enabled = abl_should_enable;
      return;
    }

    //
    // Unless this is a dry run, auto bed leveling will
    // definitely be enabled after this point
    //

    // Restore state after probing
    clean_up_after_endstop_or_probe_move();

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) DEBUG_POS("> probing complete", current_position);
    #endif

    // Calculate leveling, print reports, correct the position
    #if ENABLED(AUTO_BED_LEVELING_BILINEAR)

      if (!dryrun) extrapolate_unprobed_bed_level();
      print_bed_level();

    #elif ENABLED(AUTO_BED_LEVELING_LINEAR)

      // For LINEAR leveling calculate matrix, print reports, correct the position

      // solve lsq problem
      float plane_equation_coefficients[3];
      qr_solve(plane_equation_coefficients, abl2, 3, eqnAMatrix, eqnBVector);

      mean /= abl2;

      if (verbose_level) {
        SERIAL_PROTOCOLPGM("Eqn coefficients: a: ");
        SERIAL_PROTOCOL_F(plane_equation_coefficients[0], 8);
        SERIAL_PROTOCOLPGM(" b: ");
        SERIAL_PROTOCOL_F(plane_equation_coefficients[1], 8);
        SERIAL_PROTOCOLPGM(" d: ");
        SERIAL_PROTOCOL_F(plane_equation_coefficients[2], 8);
        SERIAL_EOL;
        if (verbose_level > 2) {
          SERIAL_PROTOCOLPGM("Mean of sampled points: ");
          SERIAL_PROTOCOL_F(mean, 8);
          SERIAL_EOL;
        }
      }

      // Create the matrix but don't correct the position yet
      if (!dryrun) {
        planner.bed_level_matrix = matrix_3x3::create_look_at(
          vector_3(-plane_equation_coefficients[0], -plane_equation_coefficients[1], 1)
        );
      }

      // Show the Topography map if enabled
      if (do_topography_map) {

        SERIAL_PROTOCOLLNPGM("\nBed Height Topography:\n"
                               "   +--- BACK --+\n"
                               "   |           |\n"
                               " L |    (+)    | R\n"
                               " E |           | I\n"
                               " F | (-) N (+) | G\n"
                               " T |           | H\n"
                               "   |    (-)    | T\n"
                               "   |           |\n"
                               "   O-- FRONT --+\n"
                               " (0,0)");

        float min_diff = 999;

        for (int8_t yy = abl_grid_points_y - 1; yy >= 0; yy--) {
          for (uint8_t xx = 0; xx < abl_grid_points_x; xx++) {
            int ind = indexIntoAB[xx][yy];
            float diff = eqnBVector[ind] - mean,
                  x_tmp = eqnAMatrix[ind + 0 * abl2],
                  y_tmp = eqnAMatrix[ind + 1 * abl2],
                  z_tmp = 0;

            apply_rotation_xyz(planner.bed_level_matrix, x_tmp, y_tmp, z_tmp);

            NOMORE(min_diff, eqnBVector[ind] - z_tmp);

            if (diff >= 0.0)
              SERIAL_PROTOCOLPGM(" +");   // Include + for column alignment
            else
              SERIAL_PROTOCOLCHAR(' ');
            SERIAL_PROTOCOL_F(diff, 5);
          } // xx
          SERIAL_EOL;
        } // yy
        SERIAL_EOL;

        if (verbose_level > 3) {
          SERIAL_PROTOCOLLNPGM("\nCorrected Bed Height vs. Bed Topology:");

          for (int8_t yy = abl_grid_points_y - 1; yy >= 0; yy--) {
            for (uint8_t xx = 0; xx < abl_grid_points_x; xx++) {
              int ind = indexIntoAB[xx][yy];
              float x_tmp = eqnAMatrix[ind + 0 * abl2],
                    y_tmp = eqnAMatrix[ind + 1 * abl2],
                    z_tmp = 0;

              apply_rotation_xyz(planner.bed_level_matrix, x_tmp, y_tmp, z_tmp);

              float diff = eqnBVector[ind] - z_tmp - min_diff;
              if (diff >= 0.0)
                SERIAL_PROTOCOLPGM(" +");
              // Include + for column alignment
              else
                SERIAL_PROTOCOLCHAR(' ');
              SERIAL_PROTOCOL_F(diff, 5);
            } // xx
            SERIAL_EOL;
          } // yy
          SERIAL_EOL;
        }
      } //do_topography_map

    #endif // AUTO_BED_LEVELING_LINEAR

    #if ABL_PLANAR

      // For LINEAR and 3POINT leveling correct the current position

      if (verbose_level > 0)
        planner.bed_level_matrix.debug("\n\nBed Level Correction Matrix:");

      if (!dryrun) {
        //
        // Correct the current XYZ position based on the tilted plane.
        //

        // 1. Get the distance from the current position to the reference point.
        float x_dist = RAW_CURRENT_POSITION(X_AXIS) - X_TILT_FULCRUM,
              y_dist = RAW_CURRENT_POSITION(Y_AXIS) - Y_TILT_FULCRUM,
              z_real = current_position[Z_AXIS],
              z_zero = 0;

        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("G29 uncorrected XYZ", current_position);
        #endif

        matrix_3x3 inverse = matrix_3x3::transpose(planner.bed_level_matrix);

        // 2. Apply the inverse matrix to the distance
        //    from the reference point to X, Y, and zero.
        apply_rotation_xyz(inverse, x_dist, y_dist, z_zero);

        // 3. Get the matrix-based corrected Z.
        //    (Even if not used, get it for comparison.)
        float new_z = z_real + z_zero;

        // 4. Use the last measured distance to the bed, if possible
        if ( NEAR(current_position[X_AXIS], xProbe - (X_PROBE_OFFSET_FROM_EXTRUDER))
          && NEAR(current_position[Y_AXIS], yProbe - (Y_PROBE_OFFSET_FROM_EXTRUDER))
        ) {
          float simple_z = z_real - (measured_z - (-zprobe_zoffset));
          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) {
              SERIAL_ECHOPAIR("Z from Probe:", simple_z);
              SERIAL_ECHOPAIR("  Matrix:", new_z);
              SERIAL_ECHOLNPAIR("  Discrepancy:", simple_z - new_z);
            }
          #endif
          new_z = simple_z;
        }

        // 5. The rotated XY and corrected Z are now current_position
        current_position[X_AXIS] = LOGICAL_X_POSITION(x_dist) + X_TILT_FULCRUM;
        current_position[Y_AXIS] = LOGICAL_Y_POSITION(y_dist) + Y_TILT_FULCRUM;
        current_position[Z_AXIS] = new_z;

        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("G29 corrected XYZ", current_position);
        #endif
      }

    #elif ENABLED(AUTO_BED_LEVELING_BILINEAR)

      if (!dryrun) {
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPAIR("G29 uncorrected Z:", current_position[Z_AXIS]);
        #endif

        // Unapply the offset because it is going to be immediately applied
        // and cause compensation movement in Z
        current_position[Z_AXIS] -= bilinear_z_offset(current_position);

        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPAIR(" corrected Z:", current_position[Z_AXIS]);
        #endif
      }

    #endif // ABL_PLANAR

    #ifdef Z_PROBE_END_SCRIPT
      #if ENABLED(DEBUG_LEVELING_FEATURE)
        if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPAIR("Z Probe End Script: ", Z_PROBE_END_SCRIPT);
      #endif
      enqueue_and_echo_commands_P(PSTR(Z_PROBE_END_SCRIPT));
      stepper.synchronize();
    #endif

    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("<<< gcode_G29");
    #endif

    report_current_position();

    KEEPALIVE_STATE(IN_HANDLER);

    // Auto Bed Leveling is complete! Enable if possible.
    planner.abl_enabled = dryrun ? abl_should_enable : true;

    if (planner.abl_enabled)
      SYNC_PLAN_POSITION_KINEMATIC();
  }

#endif // HAS_ABL

#if HAS_BED_PROBE

  /**
   * G30: Do a single Z probe at the current XY
   */
  inline void gcode_G30() {

    // Disable leveling so the planner won't mess with us
    #if PLANNER_LEVELING
      set_bed_leveling_enabled(false);
    #endif

    setup_for_endstop_or_probe_move();

    float measured_z = probe_pt(current_position[X_AXIS] + X_PROBE_OFFSET_FROM_EXTRUDER,
                                current_position[Y_AXIS] + Y_PROBE_OFFSET_FROM_EXTRUDER,
                                true, 1);

    SERIAL_PROTOCOLPGM("Bed X: ");
    SERIAL_PROTOCOL(current_position[X_AXIS] + X_PROBE_OFFSET_FROM_EXTRUDER + 0.0001);
    SERIAL_PROTOCOLPGM(" Y: ");
    SERIAL_PROTOCOL(current_position[Y_AXIS] + Y_PROBE_OFFSET_FROM_EXTRUDER + 0.0001);
    SERIAL_PROTOCOLPGM(" Z: ");
    SERIAL_PROTOCOL(measured_z + 0.0001);
    SERIAL_EOL;

    clean_up_after_endstop_or_probe_move();

    report_current_position();
  }

  #if ENABLED(Z_PROBE_SLED)

    /**
     * G31: Deploy the Z probe
     */
    inline void gcode_G31() { DEPLOY_PROBE(); }

    /**
     * G32: Stow the Z probe
     */
    inline void gcode_G32() { STOW_PROBE(); }

  #endif // Z_PROBE_SLED

#endif // HAS_BED_PROBE

#ifdef G38_2_3
  inline void gcode_G38(float code_num) { 
  #if ENABLED(Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN) || ENABLED(Z_MIN_PROBE_ENDSTOP)  //must have valid Z_MIN_PROBE definition for this command to work  
    if ((code_num == 38.2 || code_num == 38.3  ) && (code_seen('X') || code_seen('Y') || code_seen('Z'))) {
      gcode_get_destination(); // For X Y Z E F
      if (check_move()) {   // see if the commanded movement will result in a physical movement
		bool G38_pass_fail = false;
		G38_run_probe(&G38_pass_fail);
        if (!G38_pass_fail && (code_num == 38.2) ) SERIAL_PROTOCOLLNPGM(" ERROR - failed to reach target ");
      }
    }
  }
#else
 
    SERIAL_PROTOCOLLNPGM(" ERROR - Z_MIN_PROBE must be enabled ");	
  }
#endif	
#endif //G38_2_3


/**
 * G92: Set current position to given X Y Z E
 */
inline void gcode_G92() {
  bool didXYZ = false,
       didE = code_seen('E');

  if (!didE) stepper.synchronize();

  LOOP_XYZE(i) {
    if (code_seen(axis_codes[i])) {
      #if IS_SCARA
        current_position[i] = code_value_axis_units(i);
        if (i != E_AXIS) didXYZ = true;
      #else
        float p = current_position[i],
              v = code_value_axis_units(i);

        current_position[i] = v;

        if (i != E_AXIS) {
          didXYZ = true;
          position_shift[i] += v - p; // Offset the coordinate space
          update_software_endstops((AxisEnum)i);
        }
      #endif
    }
  }
  if (didXYZ)
    SYNC_PLAN_POSITION_KINEMATIC();
  else if (didE)
    sync_plan_position_e();

  report_current_position();
}

#if ENABLED(ULTIPANEL) || ENABLED(EMERGENCY_PARSER)

  /**
   * M0: Unconditional stop - Wait for user button press on LCD
   * M1: Conditional stop   - Wait for user button press on LCD
   */
  inline void gcode_M0_M1() {
    char* args = current_command_args;

    millis_t codenum = 0;
    bool hasP = false, hasS = false;
    if (code_seen('P')) {
      codenum = code_value_millis(); // milliseconds to wait
      hasP = codenum > 0;
    }
    if (code_seen('S')) {
      codenum = code_value_millis_from_seconds(); // seconds to wait
      hasS = codenum > 0;
    }

    #if ENABLED(ULTIPANEL)

      if (!hasP && !hasS && *args != '\0')
        lcd_setstatus(args, true);
      else {
        LCD_MESSAGEPGM(MSG_USERWAIT);
        #if ENABLED(LCD_PROGRESS_BAR) && PROGRESS_MSG_EXPIRE > 0
          dontExpireStatus();
        #endif
      }
      lcd_ignore_click();

    #else

      if (!hasP && !hasS && *args != '\0') {
        SERIAL_ECHO_START;
        SERIAL_ECHOLN(args);
      }

    #endif

    stepper.synchronize();
    refresh_cmd_timeout();

    #if ENABLED(ULTIPANEL)

      if (codenum > 0) {
        codenum += previous_cmd_ms;  // wait until this time for a click
        KEEPALIVE_STATE(PAUSED_FOR_USER);
        while (PENDING(millis(), codenum) && !lcd_clicked()) idle();
        lcd_ignore_click(false);
      }
      else if (lcd_detected()) {
        KEEPALIVE_STATE(PAUSED_FOR_USER);
        while (!lcd_clicked()) idle();
      }
      else return;

      if (IS_SD_PRINTING)
        LCD_MESSAGEPGM(MSG_RESUMING);
      else
        LCD_MESSAGEPGM(WELCOME_MSG);

    #else

      KEEPALIVE_STATE(PAUSED_FOR_USER);
      wait_for_user = true;

      if (codenum > 0) {
        codenum += previous_cmd_ms;  // wait until this time for an M108
        while (PENDING(millis(), codenum) && wait_for_user) idle();
      }
      else while (wait_for_user) idle();

      wait_for_user = false;

    #endif

    KEEPALIVE_STATE(IN_HANDLER);
  }

#endif // ULTIPANEL || EMERGENCY_PARSER

/**
 * M17: Enable power on all stepper motors
 */
inline void gcode_M17() {
  LCD_MESSAGEPGM(MSG_NO_MOVE);
  enable_all_steppers();
}

#if ENABLED(SDSUPPORT)

  /**
   * M20: List SD card to serial output
   */
  inline void gcode_M20() {
    SERIAL_PROTOCOLLNPGM(MSG_BEGIN_FILE_LIST);
    card.ls();
    SERIAL_PROTOCOLLNPGM(MSG_END_FILE_LIST);
  }

  /**
   * M21: Init SD Card
   */
  inline void gcode_M21() { card.initsd(); }

  /**
   * M22: Release SD Card
   */
  inline void gcode_M22() { card.release(); }

  /**
   * M23: Open a file
   */
  inline void gcode_M23() { card.openFile(current_command_args, true); }

  /**
   * M24: Start SD Print
   */
  inline void gcode_M24() {
    card.startFileprint();
    print_job_timer.start();
  }

  /**
   * M25: Pause SD Print
   */
  inline void gcode_M25() { card.pauseSDPrint(); }

  /**
   * M26: Set SD Card file index
   */
  inline void gcode_M26() {
    if (card.cardOK && code_seen('S'))
      card.setIndex(code_value_long());
  }

  /**
   * M27: Get SD Card status
   */
  inline void gcode_M27() { card.getStatus(); }

  /**
   * M28: Start SD Write
   */
  inline void gcode_M28() { card.openFile(current_command_args, false); }

  /**
   * M29: Stop SD Write
   * Processed in write to file routine above
   */
  inline void gcode_M29() {
    // card.saving = false;
  }

  /**
   * M30 <filename>: Delete SD Card file
   */
  inline void gcode_M30() {
    if (card.cardOK) {
      card.closefile();
      card.removeFile(current_command_args);
    }
  }

#endif // SDSUPPORT

/**
 * M31: Get the time since the start of SD Print (or last M109)
 */
inline void gcode_M31() {
  char buffer[21];
  duration_t elapsed = print_job_timer.duration();
  elapsed.toString(buffer);

  lcd_setstatus(buffer);

  SERIAL_ECHO_START;
  SERIAL_ECHOLNPAIR("Print time: ", buffer);

  thermalManager.autotempShutdown();
}

#if ENABLED(SDSUPPORT)

  /**
   * M32: Select file and start SD Print
   */
  inline void gcode_M32() {
    if (card.sdprinting)
      stepper.synchronize();

    char* namestartpos = strchr(current_command_args, '!');  // Find ! to indicate filename string start.
    if (!namestartpos)
      namestartpos = current_command_args; // Default name position, 4 letters after the M
    else
      namestartpos++; //to skip the '!'

    bool call_procedure = code_seen('P') && (seen_pointer < namestartpos);

    if (card.cardOK) {
      card.openFile(namestartpos, true, call_procedure);

      if (code_seen('S') && seen_pointer < namestartpos) // "S" (must occur _before_ the filename!)
        card.setIndex(code_value_long());

      card.startFileprint();

      // Procedure calls count as normal print time.
      if (!call_procedure) print_job_timer.start();
    }
  }

  #if ENABLED(LONG_FILENAME_HOST_SUPPORT)

    /**
     * M33: Get the long full path of a file or folder
     *
     * Parameters:
     *   <dospath> Case-insensitive DOS-style path to a file or folder
     *
     * Example:
     *   M33 miscel~1/armchair/armcha~1.gco
     *
     * Output:
     *   /Miscellaneous/Armchair/Armchair.gcode
     */
    inline void gcode_M33() {
      card.printLongPath(current_command_args);
    }

  #endif

  /**
   * M928: Start SD Write
   */
  inline void gcode_M928() {
    card.openLogFile(current_command_args);
  }

#endif // SDSUPPORT

/**
 * M42: Change pin status via GCode
 *
 *  P<pin>  Pin number (LED if omitted)
 *  S<byte> Pin status from 0 - 255
 */
inline void gcode_M42() {
  if (!code_seen('S')) return;

  int pin_status = code_value_int();
  if (pin_status < 0 || pin_status > 255) return;

  int pin_number = code_seen('P') ? code_value_int() : LED_PIN;
  if (pin_number < 0) return;

  for (uint8_t i = 0; i < COUNT(sensitive_pins); i++)
    if (pin_number == sensitive_pins[i]) {
      SERIAL_ERROR_START;
      SERIAL_ERRORLNPGM(MSG_ERR_PROTECTED_PIN);
      return;
    }

  pinMode(pin_number, OUTPUT);
  digitalWrite(pin_number, pin_status);
  analogWrite(pin_number, pin_status);

  #if FAN_COUNT > 0
    switch (pin_number) {
      #if HAS_FAN0
        case FAN_PIN: fanSpeeds[0] = pin_status; break;
      #endif
      #if HAS_FAN1
        case FAN1_PIN: fanSpeeds[1] = pin_status; break;
      #endif
      #if HAS_FAN2
        case FAN2_PIN: fanSpeeds[2] = pin_status; break;
      #endif
    }
  #endif
}

#if ENABLED(Z_MIN_PROBE_REPEATABILITY_TEST)

  /**
   * M48: Z probe repeatability measurement function.
   *
   * Usage:
   *   M48 <P#> <X#> <Y#> <V#> <E> <L#>
   *     P = Number of sampled points (4-50, default 10)
   *     X = Sample X position
   *     Y = Sample Y position
   *     V = Verbose level (0-4, default=1)
   *     E = Engage Z probe for each reading
   *     L = Number of legs of movement before probe
   *     S = Schizoid (Or Star if you prefer)
   *
   * This function assumes the bed has been homed.  Specifically, that a G28 command
   * as been issued prior to invoking the M48 Z probe repeatability measurement function.
   * Any information generated by a prior G29 Bed leveling command will be lost and need to be
   * regenerated.
   */
  inline void gcode_M48() {

    if (axis_unhomed_error(true, true, true)) return;

    int8_t verbose_level = code_seen('V') ? code_value_byte() : 1;
    if (verbose_level < 0 || verbose_level > 4) {
      SERIAL_PROTOCOLLNPGM("?Verbose Level not plausible (0-4).");
      return;
    }

    if (verbose_level > 0)
      SERIAL_PROTOCOLLNPGM("M48 Z-Probe Repeatability test");

    int8_t n_samples = code_seen('P') ? code_value_byte() : 10;
    if (n_samples < 4 || n_samples > 50) {
      SERIAL_PROTOCOLLNPGM("?Sample size not plausible (4-50).");
      return;
    }

    float  X_current = current_position[X_AXIS],
           Y_current = current_position[Y_AXIS];

    bool stow_probe_after_each = code_seen('E');

    float X_probe_location = code_seen('X') ? code_value_axis_units(X_AXIS) : X_current + X_PROBE_OFFSET_FROM_EXTRUDER;
    #if DISABLED(DELTA)
      if (X_probe_location < LOGICAL_X_POSITION(MIN_PROBE_X) || X_probe_location > LOGICAL_X_POSITION(MAX_PROBE_X)) {
        out_of_range_error(PSTR("X"));
        return;
      }
    #endif

    float Y_probe_location = code_seen('Y') ? code_value_axis_units(Y_AXIS) : Y_current + Y_PROBE_OFFSET_FROM_EXTRUDER;
    #if DISABLED(DELTA)
      if (Y_probe_location < LOGICAL_Y_POSITION(MIN_PROBE_Y) || Y_probe_location > LOGICAL_Y_POSITION(MAX_PROBE_Y)) {
        out_of_range_error(PSTR("Y"));
        return;
      }
    #else
      float pos[XYZ] = { X_probe_location, Y_probe_location, 0 };
      if (!position_is_reachable(pos, true)) {
        SERIAL_PROTOCOLLNPGM("? (X,Y) location outside of probeable radius.");
        return;
      }
    #endif

    bool seen_L = code_seen('L');
    uint8_t n_legs = seen_L ? code_value_byte() : 0;
    if (n_legs > 15) {
      SERIAL_PROTOCOLLNPGM("?Number of legs in movement not plausible (0-15).");
      return;
    }
    if (n_legs == 1) n_legs = 2;

    bool schizoid_flag = code_seen('S');
    if (schizoid_flag && !seen_L) n_legs = 7;

    /**
     * Now get everything to the specified probe point So we can safely do a
     * probe to get us close to the bed.  If the Z-Axis is far from the bed,
     * we don't want to use that as a starting point for each probe.
     */
    if (verbose_level > 2)
      SERIAL_PROTOCOLLNPGM("Positioning the probe...");

    // Disable bed level correction in M48 because we want the raw data when we probe
    #if HAS_ABL
      reset_bed_level();
    #endif

    setup_for_endstop_or_probe_move();

    // Move to the first point, deploy, and probe
    probe_pt(X_probe_location, Y_probe_location, stow_probe_after_each, verbose_level);

    randomSeed(millis());

    double mean = 0, sigma = 0, sample_set[n_samples];
    for (uint8_t n = 0; n < n_samples; n++) {
      if (n_legs) {
        int dir = (random(0, 10) > 5.0) ? -1 : 1;  // clockwise or counter clockwise
        float angle = random(0.0, 360.0),
              radius = random(
                #if ENABLED(DELTA)
                  DELTA_PROBEABLE_RADIUS / 8, DELTA_PROBEABLE_RADIUS / 3
                #else
                  5, X_MAX_LENGTH / 8
                #endif
              );

        if (verbose_level > 3) {
          SERIAL_ECHOPAIR("Starting radius: ", radius);
          SERIAL_ECHOPAIR("   angle: ", angle);
          SERIAL_ECHOPGM(" Direction: ");
          if (dir > 0) SERIAL_ECHOPGM("Counter-");
          SERIAL_ECHOLNPGM("Clockwise");
        }

        for (uint8_t l = 0; l < n_legs - 1; l++) {
          double delta_angle;

          if (schizoid_flag)
            // The points of a 5 point star are 72 degrees apart.  We need to
            // skip a point and go to the next one on the star.
            delta_angle = dir * 2.0 * 72.0;

          else
            // If we do this line, we are just trying to move further
            // around the circle.
            delta_angle = dir * (float) random(25, 45);

          angle += delta_angle;

          while (angle > 360.0)   // We probably do not need to keep the angle between 0 and 2*PI, but the
            angle -= 360.0;       // Arduino documentation says the trig functions should not be given values
          while (angle < 0.0)     // outside of this range.   It looks like they behave correctly with
            angle += 360.0;       // numbers outside of the range, but just to be safe we clamp them.

          X_current = X_probe_location - (X_PROBE_OFFSET_FROM_EXTRUDER) + cos(RADIANS(angle)) * radius;
          Y_current = Y_probe_location - (Y_PROBE_OFFSET_FROM_EXTRUDER) + sin(RADIANS(angle)) * radius;

          #if DISABLED(DELTA)
            X_current = constrain(X_current, X_MIN_POS, X_MAX_POS);
            Y_current = constrain(Y_current, Y_MIN_POS, Y_MAX_POS);
          #else
            // If we have gone out too far, we can do a simple fix and scale the numbers
            // back in closer to the origin.
            while (HYPOT(X_current, Y_current) > DELTA_PROBEABLE_RADIUS) {
              X_current /= 1.25;
              Y_current /= 1.25;
              if (verbose_level > 3) {
                SERIAL_ECHOPAIR("Pulling point towards center:", X_current);
                SERIAL_ECHOLNPAIR(", ", Y_current);
              }
            }
          #endif
          if (verbose_level > 3) {
            SERIAL_PROTOCOLPGM("Going to:");
            SERIAL_ECHOPAIR(" X", X_current);
            SERIAL_ECHOPAIR(" Y", Y_current);
            SERIAL_ECHOLNPAIR(" Z", current_position[Z_AXIS]);
          }
          do_blocking_move_to_xy(X_current, Y_current);
        } // n_legs loop
      } // n_legs

      // Probe a single point
      sample_set[n] = probe_pt(X_probe_location, Y_probe_location, stow_probe_after_each, verbose_level);

      /**
       * Get the current mean for the data points we have so far
       */
      double sum = 0.0;
      for (uint8_t j = 0; j <= n; j++) sum += sample_set[j];
      mean = sum / (n + 1);

      /**
       * Now, use that mean to calculate the standard deviation for the
       * data points we have so far
       */
      sum = 0.0;
      for (uint8_t j = 0; j <= n; j++)
        sum += sq(sample_set[j] - mean);

      sigma = sqrt(sum / (n + 1));
      if (verbose_level > 0) {
        if (verbose_level > 1) {
          SERIAL_PROTOCOL(n + 1);
          SERIAL_PROTOCOLPGM(" of ");
          SERIAL_PROTOCOL((int)n_samples);
          SERIAL_PROTOCOLPGM("   z: ");
          SERIAL_PROTOCOL_F(current_position[Z_AXIS], 6);
          if (verbose_level > 2) {
            SERIAL_PROTOCOLPGM(" mean: ");
            SERIAL_PROTOCOL_F(mean, 6);
            SERIAL_PROTOCOLPGM("   sigma: ");
            SERIAL_PROTOCOL_F(sigma, 6);
          }
        }
        SERIAL_EOL;
      }

    } // End of probe loop

    if (STOW_PROBE()) return;

    if (verbose_level > 0) {
      SERIAL_PROTOCOLPGM("Mean: ");
      SERIAL_PROTOCOL_F(mean, 6);
      SERIAL_EOL;
    }

    SERIAL_PROTOCOLPGM("Standard Deviation: ");
    SERIAL_PROTOCOL_F(sigma, 6);
    SERIAL_EOL; SERIAL_EOL;

    clean_up_after_endstop_or_probe_move();

    report_current_position();
  }

#endif // Z_MIN_PROBE_REPEATABILITY_TEST

/**
 * M75: Start print timer
 */
inline void gcode_M75() { print_job_timer.start(); }

/**
 * M76: Pause print timer
 */
inline void gcode_M76() { print_job_timer.pause(); }

/**
 * M77: Stop print timer
 */
inline void gcode_M77() { print_job_timer.stop(); }

#if ENABLED(PRINTCOUNTER)
  /**
   * M78: Show print statistics
   */
  inline void gcode_M78() {
    // "M78 S78" will reset the statistics
    if (code_seen('S') && code_value_int() == 78)
      print_job_timer.initStats();
    else
      print_job_timer.showStats();
  }
#endif

/**
 * M104: Set hot end temperature
 */
inline void gcode_M104() {
  if (get_target_extruder_from_command(104)) return;
  if (DEBUGGING(DRYRUN)) return;

  #if ENABLED(SINGLENOZZLE)
    if (target_extruder != active_extruder) return;
  #endif

  if (code_seen('S')) {
    thermalManager.setTargetHotend(code_value_temp_abs(), target_extruder);
    #if ENABLED(DUAL_X_CARRIAGE)
      if (dual_x_carriage_mode == DXC_DUPLICATION_MODE && target_extruder == 0)
        thermalManager.setTargetHotend(code_value_temp_abs() == 0.0 ? 0.0 : code_value_temp_abs() + duplicate_extruder_temp_offset, 1);
    #endif

    #if ENABLED(PRINTJOB_TIMER_AUTOSTART)
      /**
       * Stop the timer at the end of print, starting is managed by
       * 'heat and wait' M109.
       * We use half EXTRUDE_MINTEMP here to allow nozzles to be put into hot
       * stand by mode, for instance in a dual extruder setup, without affecting
       * the running print timer.
       */
      if (code_value_temp_abs() <= (EXTRUDE_MINTEMP)/2) {
        print_job_timer.stop();
        LCD_MESSAGEPGM(WELCOME_MSG);
      }
    #endif

    if (code_value_temp_abs() > thermalManager.degHotend(target_extruder)) LCD_MESSAGEPGM(MSG_HEATING);
  }
}

#if HAS_TEMP_HOTEND || HAS_TEMP_BED

  void print_heaterstates() {
    #if HAS_TEMP_HOTEND
      SERIAL_PROTOCOLPGM(" T:");
      SERIAL_PROTOCOL_F(thermalManager.degHotend(target_extruder), 1);
      SERIAL_PROTOCOLPGM(" /");
      SERIAL_PROTOCOL_F(thermalManager.degTargetHotend(target_extruder), 1);
      #if ENABLED(SHOW_TEMP_ADC_VALUES)
        SERIAL_PROTOCOLPAIR(" (", thermalManager.current_temperature_raw[target_extruder] / OVERSAMPLENR);
        SERIAL_CHAR(')');
      #endif
    #endif
    #if HAS_TEMP_BED
      SERIAL_PROTOCOLPGM(" B:");
      SERIAL_PROTOCOL_F(thermalManager.degBed(), 1);
      SERIAL_PROTOCOLPGM(" /");
      SERIAL_PROTOCOL_F(thermalManager.degTargetBed(), 1);
      #if ENABLED(SHOW_TEMP_ADC_VALUES)
        SERIAL_PROTOCOLPAIR(" (", thermalManager.current_temperature_bed_raw / OVERSAMPLENR);
        SERIAL_CHAR(')');
      #endif
    #endif
    #if HOTENDS > 1
      HOTEND_LOOP() {
        SERIAL_PROTOCOLPAIR(" T", e);
        SERIAL_PROTOCOLCHAR(':');
        SERIAL_PROTOCOL_F(thermalManager.degHotend(e), 1);
        SERIAL_PROTOCOLPGM(" /");
        SERIAL_PROTOCOL_F(thermalManager.degTargetHotend(e), 1);
        #if ENABLED(SHOW_TEMP_ADC_VALUES)
          SERIAL_PROTOCOLPAIR(" (", thermalManager.current_temperature_raw[e] / OVERSAMPLENR);
          SERIAL_CHAR(')');
        #endif
      }
    #endif
    SERIAL_PROTOCOLPGM(" @:");
    SERIAL_PROTOCOL(thermalManager.getHeaterPower(target_extruder));
    #if HAS_TEMP_BED
      SERIAL_PROTOCOLPGM(" B@:");
      SERIAL_PROTOCOL(thermalManager.getHeaterPower(-1));
    #endif
    #if HOTENDS > 1
      HOTEND_LOOP() {
        SERIAL_PROTOCOLPAIR(" @", e);
        SERIAL_PROTOCOLCHAR(':');
        SERIAL_PROTOCOL(thermalManager.getHeaterPower(e));
      }
    #endif
  }
#endif

/**
 * M105: Read hot end and bed temperature
 */
inline void gcode_M105() {
  if (get_target_extruder_from_command(105)) return;

  #if HAS_TEMP_HOTEND || HAS_TEMP_BED
    SERIAL_PROTOCOLPGM(MSG_OK);
    print_heaterstates();
  #else // !HAS_TEMP_HOTEND && !HAS_TEMP_BED
    SERIAL_ERROR_START;
    SERIAL_ERRORLNPGM(MSG_ERR_NO_THERMISTORS);
  #endif

  SERIAL_EOL;
}

#if FAN_COUNT > 0

  /**
   * M106: Set Fan Speed
   *
   *  S<int>   Speed between 0-255
   *  P<index> Fan index, if more than one fan
   */
  inline void gcode_M106() {
    uint16_t s = code_seen('S') ? code_value_ushort() : 255,
             p = code_seen('P') ? code_value_ushort() : 0;
    NOMORE(s, 255);
    if (p < FAN_COUNT) fanSpeeds[p] = s;
  }

  /**
   * M107: Fan Off
   */
  inline void gcode_M107() {
    uint16_t p = code_seen('P') ? code_value_ushort() : 0;
    if (p < FAN_COUNT) fanSpeeds[p] = 0;
  }

#endif // FAN_COUNT > 0

#if DISABLED(EMERGENCY_PARSER)

  /**
   * M108: Stop the waiting for heaters in M109, M190, M303. Does not affect the target temperature.
   */
  inline void gcode_M108() { wait_for_heatup = false; }


  /**
   * M112: Emergency Stop
   */
  inline void gcode_M112() { kill(PSTR(MSG_KILLED)); }


  /**
   * M410: Quickstop - Abort all planned moves
   *
   * This will stop the carriages mid-move, so most likely they
   * will be out of sync with the stepper position after this.
   */
  inline void gcode_M410() { quickstop_stepper(); }

#endif

  #ifndef MIN_COOLING_SLOPE_DEG
    #define MIN_COOLING_SLOPE_DEG 1.50
  #endif
  #ifndef MIN_COOLING_SLOPE_TIME
    #define MIN_COOLING_SLOPE_TIME 60
  #endif

/**
 * M109: Sxxx Wait for extruder(s) to reach temperature. Waits only when heating.
 *       Rxxx Wait for extruder(s) to reach temperature. Waits when heating and cooling.
 */
inline void gcode_M109() {

  if (get_target_extruder_from_command(109)) return;
  if (DEBUGGING(DRYRUN)) return;

  #if ENABLED(SINGLENOZZLE)
    if (target_extruder != active_extruder) return;
  #endif

  bool no_wait_for_cooling = code_seen('S');
  if (no_wait_for_cooling || code_seen('R')) {
    thermalManager.setTargetHotend(code_value_temp_abs(), target_extruder);
    #if ENABLED(DUAL_X_CARRIAGE)
      if (dual_x_carriage_mode == DXC_DUPLICATION_MODE && target_extruder == 0)
        thermalManager.setTargetHotend(code_value_temp_abs() == 0.0 ? 0.0 : code_value_temp_abs() + duplicate_extruder_temp_offset, 1);
    #endif

    #if ENABLED(PRINTJOB_TIMER_AUTOSTART)
      /**
       * We use half EXTRUDE_MINTEMP here to allow nozzles to be put into hot
       * stand by mode, for instance in a dual extruder setup, without affecting
       * the running print timer.
       */
      if (code_value_temp_abs() <= (EXTRUDE_MINTEMP)/2) {
        print_job_timer.stop();
        LCD_MESSAGEPGM(WELCOME_MSG);
      }
      /**
       * We do not check if the timer is already running because this check will
       * be done for us inside the Stopwatch::start() method thus a running timer
       * will not restart.
       */
      else print_job_timer.start();
    #endif

    if (thermalManager.isHeatingHotend(target_extruder)) LCD_MESSAGEPGM(MSG_HEATING);
  }

  #if ENABLED(AUTOTEMP)
    planner.autotemp_M109();
  #endif

  #if TEMP_RESIDENCY_TIME > 0
    millis_t residency_start_ms = 0;
    // Loop until the temperature has stabilized
    #define TEMP_CONDITIONS (!residency_start_ms || PENDING(now, residency_start_ms + (TEMP_RESIDENCY_TIME) * 1000UL))
  #else
    // Loop until the temperature is very close target
    #define TEMP_CONDITIONS (wants_to_cool ? thermalManager.isCoolingHotend(target_extruder) : thermalManager.isHeatingHotend(target_extruder))
  #endif //TEMP_RESIDENCY_TIME > 0

  float theTarget = -1.0, old_temp = 9999.0;
  bool wants_to_cool = false;
  wait_for_heatup = true;
  millis_t now, next_temp_ms = 0, next_cool_check_ms = 0;

  KEEPALIVE_STATE(NOT_BUSY);

  do {
    // Target temperature might be changed during the loop
    if (theTarget != thermalManager.degTargetHotend(target_extruder)) {
      wants_to_cool = thermalManager.isCoolingHotend(target_extruder);
      theTarget = thermalManager.degTargetHotend(target_extruder);

      // Exit if S<lower>, continue if S<higher>, R<lower>, or R<higher>
      if (no_wait_for_cooling && wants_to_cool) break;
    }

    now = millis();
    if (ELAPSED(now, next_temp_ms)) { //Print temp & remaining time every 1s while waiting
      next_temp_ms = now + 1000UL;
      print_heaterstates();
      #if TEMP_RESIDENCY_TIME > 0
        SERIAL_PROTOCOLPGM(" W:");
        if (residency_start_ms) {
          long rem = (((TEMP_RESIDENCY_TIME) * 1000UL) - (now - residency_start_ms)) / 1000UL;
          SERIAL_PROTOCOLLN(rem);
        }
        else {
          SERIAL_PROTOCOLLNPGM("?");
        }
      #else
        SERIAL_EOL;
      #endif
    }

    idle();
    refresh_cmd_timeout(); // to prevent stepper_inactive_time from running out

    float temp = thermalManager.degHotend(target_extruder);

    #if TEMP_RESIDENCY_TIME > 0

      float temp_diff = fabs(theTarget - temp);

      if (!residency_start_ms) {
        // Start the TEMP_RESIDENCY_TIME timer when we reach target temp for the first time.
        if (temp_diff < TEMP_WINDOW) residency_start_ms = now;
      }
      else if (temp_diff > TEMP_HYSTERESIS) {
        // Restart the timer whenever the temperature falls outside the hysteresis.
        residency_start_ms = now;
      }

    #endif //TEMP_RESIDENCY_TIME > 0

    // Prevent a wait-forever situation if R is misused i.e. M109 R0
    if (wants_to_cool) {
      // break after MIN_COOLING_SLOPE_TIME seconds
      // if the temperature did not drop at least MIN_COOLING_SLOPE_DEG
      if (!next_cool_check_ms || ELAPSED(now, next_cool_check_ms)) {
        if (old_temp - temp < MIN_COOLING_SLOPE_DEG) break;
        next_cool_check_ms = now + 1000UL * MIN_COOLING_SLOPE_TIME;
        old_temp = temp;
      }
    }

  } while (wait_for_heatup && TEMP_CONDITIONS);

  if (wait_for_heatup) LCD_MESSAGEPGM(MSG_HEATING_COMPLETE);

  KEEPALIVE_STATE(IN_HANDLER);
}

#if HAS_TEMP_BED

  #ifndef MIN_COOLING_SLOPE_DEG_BED
    #define MIN_COOLING_SLOPE_DEG_BED 1.50
  #endif
  #ifndef MIN_COOLING_SLOPE_TIME_BED
    #define MIN_COOLING_SLOPE_TIME_BED 60
  #endif

  /**
   * M190: Sxxx Wait for bed current temp to reach target temp. Waits only when heating
   *       Rxxx Wait for bed current temp to reach target temp. Waits when heating and cooling
   */
  inline void gcode_M190() {
    if (DEBUGGING(DRYRUN)) return;

    LCD_MESSAGEPGM(MSG_BED_HEATING);
    bool no_wait_for_cooling = code_seen('S');
    if (no_wait_for_cooling || code_seen('R')) {
      thermalManager.setTargetBed(code_value_temp_abs());
      #if ENABLED(PRINTJOB_TIMER_AUTOSTART)
        if (code_value_temp_abs() > BED_MINTEMP) {
          /**
          * We start the timer when 'heating and waiting' command arrives, LCD
          * functions never wait. Cooling down managed by extruders.
          *
          * We do not check if the timer is already running because this check will
          * be done for us inside the Stopwatch::start() method thus a running timer
          * will not restart.
          */
          print_job_timer.start();
        }
      #endif
    }

    #if TEMP_BED_RESIDENCY_TIME > 0
      millis_t residency_start_ms = 0;
      // Loop until the temperature has stabilized
      #define TEMP_BED_CONDITIONS (!residency_start_ms || PENDING(now, residency_start_ms + (TEMP_BED_RESIDENCY_TIME) * 1000UL))
    #else
      // Loop until the temperature is very close target
      #define TEMP_BED_CONDITIONS (wants_to_cool ? thermalManager.isCoolingBed() : thermalManager.isHeatingBed())
    #endif //TEMP_BED_RESIDENCY_TIME > 0

    float theTarget = -1.0, old_temp = 9999.0;
    bool wants_to_cool = false;
    wait_for_heatup = true;
    millis_t now, next_temp_ms = 0, next_cool_check_ms = 0;

    KEEPALIVE_STATE(NOT_BUSY);

    target_extruder = active_extruder; // for print_heaterstates

    do {
      // Target temperature might be changed during the loop
      if (theTarget != thermalManager.degTargetBed()) {
        wants_to_cool = thermalManager.isCoolingBed();
        theTarget = thermalManager.degTargetBed();

        // Exit if S<lower>, continue if S<higher>, R<lower>, or R<higher>
        if (no_wait_for_cooling && wants_to_cool) break;
      }

      now = millis();
      if (ELAPSED(now, next_temp_ms)) { //Print Temp Reading every 1 second while heating up.
        next_temp_ms = now + 1000UL;
        print_heaterstates();
        #if TEMP_BED_RESIDENCY_TIME > 0
          SERIAL_PROTOCOLPGM(" W:");
          if (residency_start_ms) {
            long rem = (((TEMP_BED_RESIDENCY_TIME) * 1000UL) - (now - residency_start_ms)) / 1000UL;
            SERIAL_PROTOCOLLN(rem);
          }
          else {
            SERIAL_PROTOCOLLNPGM("?");
          }
        #else
          SERIAL_EOL;
        #endif
      }

      idle();
      refresh_cmd_timeout(); // to prevent stepper_inactive_time from running out

      float temp = thermalManager.degBed();

      #if TEMP_BED_RESIDENCY_TIME > 0

        float temp_diff = fabs(theTarget - temp);

        if (!residency_start_ms) {
          // Start the TEMP_BED_RESIDENCY_TIME timer when we reach target temp for the first time.
          if (temp_diff < TEMP_BED_WINDOW) residency_start_ms = now;
        }
        else if (temp_diff > TEMP_BED_HYSTERESIS) {
          // Restart the timer whenever the temperature falls outside the hysteresis.
          residency_start_ms = now;
        }

      #endif //TEMP_BED_RESIDENCY_TIME > 0

      // Prevent a wait-forever situation if R is misused i.e. M190 R0
      if (wants_to_cool) {
        // break after MIN_COOLING_SLOPE_TIME_BED seconds
        // if the temperature did not drop at least MIN_COOLING_SLOPE_DEG_BED
        if (!next_cool_check_ms || ELAPSED(now, next_cool_check_ms)) {
          if (old_temp - temp < MIN_COOLING_SLOPE_DEG_BED) break;
          next_cool_check_ms = now + 1000UL * MIN_COOLING_SLOPE_TIME_BED;
          old_temp = temp;
        }
      }

    } while (wait_for_heatup && TEMP_BED_CONDITIONS);

    if (wait_for_heatup) LCD_MESSAGEPGM(MSG_BED_DONE);
    KEEPALIVE_STATE(IN_HANDLER);
  }

#endif // HAS_TEMP_BED

/**
 * M110: Set Current Line Number
 */
inline void gcode_M110() {
  if (code_seen('N')) gcode_N = code_value_long();
}

/**
 * M111: Set the debug level
 */
inline void gcode_M111() {
  marlin_debug_flags = code_seen('S') ? code_value_byte() : (uint8_t) DEBUG_NONE;

  const static char str_debug_1[] PROGMEM = MSG_DEBUG_ECHO;
  const static char str_debug_2[] PROGMEM = MSG_DEBUG_INFO;
  const static char str_debug_4[] PROGMEM = MSG_DEBUG_ERRORS;
  const static char str_debug_8[] PROGMEM = MSG_DEBUG_DRYRUN;
  const static char str_debug_16[] PROGMEM = MSG_DEBUG_COMMUNICATION;
  #if ENABLED(DEBUG_LEVELING_FEATURE)
    const static char str_debug_32[] PROGMEM = MSG_DEBUG_LEVELING;
  #endif

  const static char* const debug_strings[] PROGMEM = {
    str_debug_1, str_debug_2, str_debug_4, str_debug_8, str_debug_16,
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      str_debug_32
    #endif
  };

  SERIAL_ECHO_START;
  SERIAL_ECHOPGM(MSG_DEBUG_PREFIX);
  if (marlin_debug_flags) {
    uint8_t comma = 0;
    for (uint8_t i = 0; i < COUNT(debug_strings); i++) {
      if (TEST(marlin_debug_flags, i)) {
        if (comma++) SERIAL_CHAR(',');
        serialprintPGM((char*)pgm_read_word(&(debug_strings[i])));
      }
    }
  }
  else {
    SERIAL_ECHOPGM(MSG_DEBUG_OFF);
  }
  SERIAL_EOL;
}

#if ENABLED(HOST_KEEPALIVE_FEATURE)

  /**
   * M113: Get or set Host Keepalive interval (0 to disable)
   *
   *   S<seconds> Optional. Set the keepalive interval.
   */
  inline void gcode_M113() {
    if (code_seen('S')) {
      host_keepalive_interval = code_value_byte();
      NOMORE(host_keepalive_interval, 60);
    }
    else {
      SERIAL_ECHO_START;
      SERIAL_ECHOLNPAIR("M113 S", (unsigned long)host_keepalive_interval);
    }
  }

#endif

#if ENABLED(BARICUDA)

  #if HAS_HEATER_1
    /**
     * M126: Heater 1 valve open
     */
    inline void gcode_M126() { baricuda_valve_pressure = code_seen('S') ? code_value_byte() : 255; }
    /**
     * M127: Heater 1 valve close
     */
    inline void gcode_M127() { baricuda_valve_pressure = 0; }
  #endif

  #if HAS_HEATER_2
    /**
     * M128: Heater 2 valve open
     */
    inline void gcode_M128() { baricuda_e_to_p_pressure = code_seen('S') ? code_value_byte() : 255; }
    /**
     * M129: Heater 2 valve close
     */
    inline void gcode_M129() { baricuda_e_to_p_pressure = 0; }
  #endif

#endif //BARICUDA

/**
 * M140: Set bed temperature
 */
inline void gcode_M140() {
  if (DEBUGGING(DRYRUN)) return;
  if (code_seen('S')) thermalManager.setTargetBed(code_value_temp_abs());
}

#if ENABLED(ULTIPANEL)

  /**
   * M145: Set the heatup state for a material in the LCD menu
   *   S<material> (0=PLA, 1=ABS)
   *   H<hotend temp>
   *   B<bed temp>
   *   F<fan speed>
   */
  inline void gcode_M145() {
    int8_t material = code_seen('S') ? (int8_t)code_value_int() : 0;
    if (material < 0 || material > 1) {
      SERIAL_ERROR_START;
      SERIAL_ERRORLNPGM(MSG_ERR_MATERIAL_INDEX);
    }
    else {
      int v;
      switch (material) {
        case 0:
          if (code_seen('H')) {
            v = code_value_int();
            preheatHotendTemp1 = constrain(v, EXTRUDE_MINTEMP, HEATER_0_MAXTEMP - 15);
          }
          if (code_seen('F')) {
            v = code_value_int();
            preheatFanSpeed1 = constrain(v, 0, 255);
          }
          #if TEMP_SENSOR_BED != 0
            if (code_seen('B')) {
              v = code_value_int();
              preheatBedTemp1 = constrain(v, BED_MINTEMP, BED_MAXTEMP - 15);
            }
          #endif
          break;
        case 1:
          if (code_seen('H')) {
            v = code_value_int();
            preheatHotendTemp2 = constrain(v, EXTRUDE_MINTEMP, HEATER_0_MAXTEMP - 15);
          }
          if (code_seen('F')) {
            v = code_value_int();
            preheatFanSpeed2 = constrain(v, 0, 255);
          }
          #if TEMP_SENSOR_BED != 0
            if (code_seen('B')) {
              v = code_value_int();
              preheatBedTemp2 = constrain(v, BED_MINTEMP, BED_MAXTEMP - 15);
            }
          #endif
          break;
      }
    }
  }

#endif // ULTIPANEL

#if ENABLED(TEMPERATURE_UNITS_SUPPORT)
  /**
   * M149: Set temperature units
   */
  inline void gcode_M149() {
    if (code_seen('C')) {
      set_input_temp_units(TEMPUNIT_C);
    } else if (code_seen('K')) {
      set_input_temp_units(TEMPUNIT_K);
    } else if (code_seen('F')) {
      set_input_temp_units(TEMPUNIT_F);
    }
  }
#endif

#if HAS_POWER_SWITCH

  /**
   * M80: Turn on Power Supply
   */
  inline void gcode_M80() {
    OUT_WRITE(PS_ON_PIN, PS_ON_AWAKE); //GND

    /**
     * If you have a switch on suicide pin, this is useful
     * if you want to start another print with suicide feature after
     * a print without suicide...
     */
    #if HAS_SUICIDE
      OUT_WRITE(SUICIDE_PIN, HIGH);
    #endif

    #if ENABLED(ULTIPANEL)
      powersupply = true;
      LCD_MESSAGEPGM(WELCOME_MSG);
      lcd_update();
    #endif
  }

#endif // HAS_POWER_SWITCH

/**
 * M81: Turn off Power, including Power Supply, if there is one.
 *
 *      This code should ALWAYS be available for EMERGENCY SHUTDOWN!
 */
inline void gcode_M81() {
  thermalManager.disable_all_heaters();
  stepper.finish_and_disable();
  #if FAN_COUNT > 0
    #if FAN_COUNT > 1
      for (uint8_t i = 0; i < FAN_COUNT; i++) fanSpeeds[i] = 0;
    #else
      fanSpeeds[0] = 0;
    #endif
  #endif
  delay(1000); // Wait 1 second before switching off
  #if HAS_SUICIDE
    stepper.synchronize();
    suicide();
  #elif HAS_POWER_SWITCH
    OUT_WRITE(PS_ON_PIN, PS_ON_ASLEEP);
  #endif
  #if ENABLED(ULTIPANEL)
    #if HAS_POWER_SWITCH
      powersupply = false;
    #endif
    LCD_MESSAGEPGM(MACHINE_NAME " " MSG_OFF ".");
    lcd_update();
  #endif
}

/**
 * M82: Set E codes absolute (default)
 */
inline void gcode_M82() { axis_relative_modes[E_AXIS] = false; }

/**
 * M83: Set E codes relative while in Absolute Coordinates (G90) mode
 */
inline void gcode_M83() { axis_relative_modes[E_AXIS] = true; }

/**
 * M18, M84: Disable all stepper motors
 */
inline void gcode_M18_M84() {
  if (code_seen('S')) {
    stepper_inactive_time = code_value_millis_from_seconds();
  }
  else {
    bool all_axis = !((code_seen('X')) || (code_seen('Y')) || (code_seen('Z')) || (code_seen('E')));
    if (all_axis) {
      stepper.finish_and_disable();
    }
    else {
      stepper.synchronize();
      if (code_seen('X')) disable_x();
      if (code_seen('Y')) disable_y();
      if (code_seen('Z')) disable_z();
      #if ((E0_ENABLE_PIN != X_ENABLE_PIN) && (E1_ENABLE_PIN != Y_ENABLE_PIN)) // Only enable on boards that have seperate ENABLE_PINS
        if (code_seen('E')) {
          disable_e0();
          disable_e1();
          disable_e2();
          disable_e3();
        }
      #endif
    }
  }
}

/**
 * M85: Set inactivity shutdown timer with parameter S<seconds>. To disable set zero (default)
 */
inline void gcode_M85() {
  if (code_seen('S')) max_inactive_time = code_value_millis_from_seconds();
}

/**
 * M92: Set axis steps-per-unit for one or more axes, X, Y, Z, and E.
 *      (Follows the same syntax as G92)
 */
inline void gcode_M92() {
  LOOP_XYZE(i) {
    if (code_seen(axis_codes[i])) {
      if (i == E_AXIS) {
        float value = code_value_per_axis_unit(i);
        if (value < 20.0) {
          float factor = planner.axis_steps_per_mm[i] / value; // increase e constants if M92 E14 is given for netfab.
          planner.max_e_jerk *= factor;
          planner.max_feedrate_mm_s[i] *= factor;
          planner.max_acceleration_steps_per_s2[i] *= factor;
        }
        planner.axis_steps_per_mm[i] = value;
      }
      else {
        planner.axis_steps_per_mm[i] = code_value_per_axis_unit(i);
      }
    }
  }
  planner.refresh_positioning();
}

/**
 * Output the current position to serial
 */
static void report_current_position() {
  SERIAL_PROTOCOLPGM("X:");
  SERIAL_PROTOCOL(current_position[X_AXIS]);
  SERIAL_PROTOCOLPGM(" Y:");
  SERIAL_PROTOCOL(current_position[Y_AXIS]);
  SERIAL_PROTOCOLPGM(" Z:");
  SERIAL_PROTOCOL(current_position[Z_AXIS]);
  SERIAL_PROTOCOLPGM(" E:");
  SERIAL_PROTOCOL(current_position[E_AXIS]);

  stepper.report_positions();

  #if IS_SCARA
    SERIAL_PROTOCOLPAIR("SCARA Theta:", stepper.get_axis_position_degrees(A_AXIS));
    SERIAL_PROTOCOLLNPAIR("   Psi+Theta:", stepper.get_axis_position_degrees(B_AXIS));
    SERIAL_EOL;
  #endif
}

/**
 * M114: Output current position to serial port
 */
inline void gcode_M114() { report_current_position(); }

/**
 * M115: Capabilities string
 */
inline void gcode_M115() {
  SERIAL_PROTOCOLPGM(MSG_M115_REPORT);
}

/**
 * M117: Set LCD Status Message
 */
inline void gcode_M117() {
  lcd_setstatus(current_command_args);
}

/**
 * M119: Output endstop states to serial output
 */
inline void gcode_M119() { endstops.M119(); }

/**
 * M120: Enable endstops and set non-homing endstop state to "enabled"
 */
inline void gcode_M120() { endstops.enable_globally(true); }

/**
 * M121: Disable endstops and set non-homing endstop state to "disabled"
 */
inline void gcode_M121() { endstops.enable_globally(false); }

#if ENABLED(BLINKM)

  /**
   * M150: Set Status LED Color - Use R-U-B for R-G-B
   */
  inline void gcode_M150() {
    SendColors(
      code_seen('R') ? code_value_byte() : 0,
      code_seen('U') ? code_value_byte() : 0,
      code_seen('B') ? code_value_byte() : 0
    );
  }

#endif // BLINKM

#if ENABLED(EXPERIMENTAL_I2CBUS)

  /**
   * M155: Send data to a I2C slave device
   *
   * This is a PoC, the formating and arguments for the GCODE will
   * change to be more compatible, the current proposal is:
   *
   *  M155 A<slave device address base 10> ; Sets the I2C slave address the data will be sent to
   *
   *  M155 B<byte-1 value in base 10>
   *  M155 B<byte-2 value in base 10>
   *  M155 B<byte-3 value in base 10>
   *
   *  M155 S1 ; Send the buffered data and reset the buffer
   *  M155 R1 ; Reset the buffer without sending data
   *
   */
  inline void gcode_M155() {
    // Set the target address
    if (code_seen('A')) i2c.address(code_value_byte());

    // Add a new byte to the buffer
    if (code_seen('B')) i2c.addbyte(code_value_byte());

    // Flush the buffer to the bus
    if (code_seen('S')) i2c.send();

    // Reset and rewind the buffer
    else if (code_seen('R')) i2c.reset();
  }

  /**
   * M156: Request X bytes from I2C slave device
   *
   * Usage: M156 A<slave device address base 10> B<number of bytes>
   */
  inline void gcode_M156() {
    if (code_seen('A')) i2c.address(code_value_byte());

    uint8_t bytes = code_seen('B') ? code_value_byte() : 1;

    if (i2c.addr && bytes && bytes <= TWIBUS_BUFFER_SIZE) {
      i2c.relay(bytes);
    }
    else {
      SERIAL_ERROR_START;
      SERIAL_ERRORLN("Bad i2c request");
    }
  }

#endif // EXPERIMENTAL_I2CBUS

/**
 * M200: Set filament diameter and set E axis units to cubic units
 *
 *    T<extruder> - Optional extruder number. Current extruder if omitted.
 *    D<linear> - Diameter of the filament. Use "D0" to switch back to linear units on the E axis.
 */
inline void gcode_M200() {

  if (get_target_extruder_from_command(200)) return;

  if (code_seen('D')) {
    // setting any extruder filament size disables volumetric on the assumption that
    // slicers either generate in extruder values as cubic mm or as as filament feeds
    // for all extruders
    volumetric_enabled = (code_value_linear_units() != 0.0);
    if (volumetric_enabled) {
      filament_size[target_extruder] = code_value_linear_units();
      // make sure all extruders have some sane value for the filament size
      for (uint8_t i = 0; i < COUNT(filament_size); i++)
        if (! filament_size[i]) filament_size[i] = DEFAULT_NOMINAL_FILAMENT_DIA;
    }
  }
  else {
    //reserved for setting filament diameter via UFID or filament measuring device
    return;
  }
  calculate_volumetric_multipliers();
}

/**
 * M201: Set max acceleration in units/s^2 for print moves (M201 X1000 Y1000)
 */
inline void gcode_M201() {
  LOOP_XYZE(i) {
    if (code_seen(axis_codes[i])) {
      planner.max_acceleration_mm_per_s2[i] = code_value_axis_units(i);
    }
  }
  // steps per sq second need to be updated to agree with the units per sq second (as they are what is used in the planner)
  planner.reset_acceleration_rates();
}

#if 0 // Not used for Sprinter/grbl gen6
  inline void gcode_M202() {
    LOOP_XYZE(i) {
      if (code_seen(axis_codes[i])) axis_travel_steps_per_sqr_second[i] = code_value_axis_units(i) * planner.axis_steps_per_mm[i];
    }
  }
#endif


/**
 * M203: Set maximum feedrate that your machine can sustain (M203 X200 Y200 Z300 E10000) in units/sec
 */
inline void gcode_M203() {
  LOOP_XYZE(i)
    if (code_seen(axis_codes[i]))
      planner.max_feedrate_mm_s[i] = code_value_axis_units(i);
}

/**
 * M204: Set Accelerations in units/sec^2 (M204 P1200 R3000 T3000)
 *
 *    P = Printing moves
 *    R = Retract only (no X, Y, Z) moves
 *    T = Travel (non printing) moves
 *
 *  Also sets minimum segment time in ms (B20000) to prevent buffer under-runs and M20 minimum feedrate
 */
inline void gcode_M204() {
  if (code_seen('S')) {  // Kept for legacy compatibility. Should NOT BE USED for new developments.
    planner.travel_acceleration = planner.acceleration = code_value_linear_units();
    SERIAL_ECHOLNPAIR("Setting Print and Travel Acceleration: ", planner.acceleration);
  }
  if (code_seen('P')) {
    planner.acceleration = code_value_linear_units();
    SERIAL_ECHOLNPAIR("Setting Print Acceleration: ", planner.acceleration);
  }
  if (code_seen('R')) {
    planner.retract_acceleration = code_value_linear_units();
    SERIAL_ECHOLNPAIR("Setting Retract Acceleration: ", planner.retract_acceleration);
  }
  if (code_seen('T')) {
    planner.travel_acceleration = code_value_linear_units();
    SERIAL_ECHOLNPAIR("Setting Travel Acceleration: ", planner.travel_acceleration);
  }
}

/**
 * M205: Set Advanced Settings
 *
 *    S = Min Feed Rate (units/s)
 *    T = Min Travel Feed Rate (units/s)
 *    B = Min Segment Time (µs)
 *    X = Max XY Jerk (units/sec^2)
 *    Z = Max Z Jerk (units/sec^2)
 *    E = Max E Jerk (units/sec^2)
 */
inline void gcode_M205() {
  if (code_seen('S')) planner.min_feedrate_mm_s = code_value_linear_units();
  if (code_seen('T')) planner.min_travel_feedrate_mm_s = code_value_linear_units();
  if (code_seen('B')) planner.min_segment_time = code_value_millis();
  if (code_seen('X')) planner.max_xy_jerk = code_value_linear_units();
  if (code_seen('Z')) planner.max_z_jerk = code_value_axis_units(Z_AXIS);
  if (code_seen('E')) planner.max_e_jerk = code_value_axis_units(E_AXIS);
}

/**
 * M206: Set Additional Homing Offset (X Y Z). SCARA aliases T=X, P=Y
 */
inline void gcode_M206() {
  LOOP_XYZ(i)
    if (code_seen(axis_codes[i]))
      set_home_offset((AxisEnum)i, code_value_axis_units(i));

  #if ENABLED(MORGAN_SCARA)
    if (code_seen('T')) set_home_offset(A_AXIS, code_value_axis_units(A_AXIS)); // Theta
    if (code_seen('P')) set_home_offset(B_AXIS, code_value_axis_units(B_AXIS)); // Psi
  #endif

  SYNC_PLAN_POSITION_KINEMATIC();
  report_current_position();
}

#if ENABLED(DELTA)
  /**
   * M665: Set delta configurations
   *
   *    L = diagonal rod
   *    R = delta radius
   *    S = segments per second
   *    A = Alpha (Tower 1) diagonal rod trim
   *    B = Beta (Tower 2) diagonal rod trim
   *    C = Gamma (Tower 3) diagonal rod trim
   */
  inline void gcode_M665() {
    if (code_seen('L')) delta_diagonal_rod = code_value_linear_units();
    if (code_seen('R')) delta_radius = code_value_linear_units();
    if (code_seen('S')) delta_segments_per_second = code_value_float();
    if (code_seen('A')) delta_diagonal_rod_trim_tower_1 = code_value_linear_units();
    if (code_seen('B')) delta_diagonal_rod_trim_tower_2 = code_value_linear_units();
    if (code_seen('C')) delta_diagonal_rod_trim_tower_3 = code_value_linear_units();
    recalc_delta_settings(delta_radius, delta_diagonal_rod);
  }
  /**
   * M666: Set delta endstop adjustment
   */
  inline void gcode_M666() {
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOLNPGM(">>> gcode_M666");
      }
    #endif
    LOOP_XYZ(i) {
      if (code_seen(axis_codes[i])) {
        endstop_adj[i] = code_value_axis_units(i);
        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) {
            SERIAL_ECHOPAIR("endstop_adj[", axis_codes[i]);
            SERIAL_ECHOLNPAIR("] = ", endstop_adj[i]);
          }
        #endif
      }
    }
    #if ENABLED(DEBUG_LEVELING_FEATURE)
      if (DEBUGGING(LEVELING)) {
        SERIAL_ECHOLNPGM("<<< gcode_M666");
      }
    #endif
  }

#elif ENABLED(Z_DUAL_ENDSTOPS) // !DELTA && ENABLED(Z_DUAL_ENDSTOPS)

  /**
   * M666: For Z Dual Endstop setup, set z axis offset to the z2 axis.
   */
  inline void gcode_M666() {
    if (code_seen('Z')) z_endstop_adj = code_value_axis_units(Z_AXIS);
    SERIAL_ECHOLNPAIR("Z Endstop Adjustment set to (mm):", z_endstop_adj);
  }

#endif // !DELTA && Z_DUAL_ENDSTOPS

#if ENABLED(FWRETRACT)

  /**
   * M207: Set firmware retraction values
   *
   *   S[+units]    retract_length
   *   W[+units]    retract_length_swap (multi-extruder)
   *   F[units/min] retract_feedrate_mm_s
   *   Z[units]     retract_zlift
   */
  inline void gcode_M207() {
    if (code_seen('S')) retract_length = code_value_axis_units(E_AXIS);
    if (code_seen('F')) retract_feedrate_mm_s = MMM_TO_MMS(code_value_axis_units(E_AXIS));
    if (code_seen('Z')) retract_zlift = code_value_axis_units(Z_AXIS);
    #if EXTRUDERS > 1
      if (code_seen('W')) retract_length_swap = code_value_axis_units(E_AXIS);
    #endif
  }

  /**
   * M208: Set firmware un-retraction values
   *
   *   S[+units]    retract_recover_length (in addition to M207 S*)
   *   W[+units]    retract_recover_length_swap (multi-extruder)
   *   F[units/min] retract_recover_feedrate_mm_s
   */
  inline void gcode_M208() {
    if (code_seen('S')) retract_recover_length = code_value_axis_units(E_AXIS);
    if (code_seen('F')) retract_recover_feedrate_mm_s = MMM_TO_MMS(code_value_axis_units(E_AXIS));
    #if EXTRUDERS > 1
      if (code_seen('W')) retract_recover_length_swap = code_value_axis_units(E_AXIS);
    #endif
  }

  /**
   * M209: Enable automatic retract (M209 S1)
   *       detect if the slicer did not support G10/11: every normal extrude-only move will be classified as retract depending on the direction.
   */
  inline void gcode_M209() {
    if (code_seen('S')) {
      autoretract_enabled = code_value_bool();
      for (int i = 0; i < EXTRUDERS; i++) retracted[i] = false;
    }
  }

#endif // FWRETRACT

/**
 * M211: Enable, Disable, and/or Report software endstops
 *
 * Usage: M211 S1 to enable, M211 S0 to disable, M211 alone for report
 */
inline void gcode_M211() {
  SERIAL_ECHO_START;
  #if ENABLED(min_software_endstops) || ENABLED(max_software_endstops)
    if (code_seen('S')) soft_endstops_enabled = code_value_bool();
  #endif
  #if ENABLED(min_software_endstops) || ENABLED(max_software_endstops)
    SERIAL_ECHOPGM(MSG_SOFT_ENDSTOPS);
    serialprintPGM(soft_endstops_enabled ? PSTR(MSG_ON) : PSTR(MSG_OFF));
  #else
    SERIAL_ECHOPGM(MSG_SOFT_ENDSTOPS);
    SERIAL_ECHOPGM(MSG_OFF);
  #endif
  SERIAL_ECHOPGM(MSG_SOFT_MIN);
  SERIAL_ECHOPAIR(    MSG_X, soft_endstop_min[X_AXIS]);
  SERIAL_ECHOPAIR(" " MSG_Y, soft_endstop_min[Y_AXIS]);
  SERIAL_ECHOPAIR(" " MSG_Z, soft_endstop_min[Z_AXIS]);
  SERIAL_ECHOPGM(MSG_SOFT_MAX);
  SERIAL_ECHOPAIR(    MSG_X, soft_endstop_max[X_AXIS]);
  SERIAL_ECHOPAIR(" " MSG_Y, soft_endstop_max[Y_AXIS]);
  SERIAL_ECHOLNPAIR(" " MSG_Z, soft_endstop_max[Z_AXIS]);
}

#if HOTENDS > 1

  /**
   * M218 - set hotend offset (in linear units)
   *
   *   T<tool>
   *   X<xoffset>
   *   Y<yoffset>
   *   Z<zoffset> - Available with DUAL_X_CARRIAGE and SWITCHING_EXTRUDER
   */
  inline void gcode_M218() {
    if (get_target_extruder_from_command(218)) return;

    if (code_seen('X')) hotend_offset[X_AXIS][target_extruder] = code_value_axis_units(X_AXIS);
    if (code_seen('Y')) hotend_offset[Y_AXIS][target_extruder] = code_value_axis_units(Y_AXIS);

    #if ENABLED(DUAL_X_CARRIAGE) || ENABLED(SWITCHING_EXTRUDER)
      if (code_seen('Z')) hotend_offset[Z_AXIS][target_extruder] = code_value_axis_units(Z_AXIS);
    #endif

    SERIAL_ECHO_START;
    SERIAL_ECHOPGM(MSG_HOTEND_OFFSET);
    HOTEND_LOOP() {
      SERIAL_CHAR(' ');
      SERIAL_ECHO(hotend_offset[X_AXIS][e]);
      SERIAL_CHAR(',');
      SERIAL_ECHO(hotend_offset[Y_AXIS][e]);
      #if ENABLED(DUAL_X_CARRIAGE) || ENABLED(SWITCHING_EXTRUDER)
        SERIAL_CHAR(',');
        SERIAL_ECHO(hotend_offset[Z_AXIS][e]);
      #endif
    }
    SERIAL_EOL;
  }

#endif // HOTENDS > 1

/**
 * M220: Set speed percentage factor, aka "Feed Rate" (M220 S95)
 */
inline void gcode_M220() {
  if (code_seen('S')) feedrate_percentage = code_value_int();
}

/**
 * M221: Set extrusion percentage (M221 T0 S95)
 */
inline void gcode_M221() {
  if (get_target_extruder_from_command(221)) return;
  if (code_seen('S'))
    flow_percentage[target_extruder] = code_value_int();
}

/**
 * M226: Wait until the specified pin reaches the state required (M226 P<pin> S<state>)
 */
inline void gcode_M226() {
  if (code_seen('P')) {
    int pin_number = code_value_int();
    int pin_state = code_seen('S') ? code_value_int() : -1; // required pin state - default is inverted

    if (pin_state >= -1 && pin_state <= 1) {

      for (uint8_t i = 0; i < COUNT(sensitive_pins); i++) {
        if (sensitive_pins[i] == pin_number) {
          pin_number = -1;
          break;
        }
      }

      if (pin_number > -1) {
        int target = LOW;

        stepper.synchronize();

        pinMode(pin_number, INPUT);

        switch (pin_state) {
          case 1:
            target = HIGH;
            break;

          case 0:
            target = LOW;
            break;

          case -1:
            target = !digitalRead(pin_number);
            break;
        }

        while (digitalRead(pin_number) != target) idle();

      } // pin_number > -1
    } // pin_state -1 0 1
  } // code_seen('P')
}

#if HAS_SERVOS

  /**
   * M280: Get or set servo position. P<index> [S<angle>]
   */
  inline void gcode_M280() {
    if (!code_seen('P')) return;
    int servo_index = code_value_int();
    if (servo_index >= 0 && servo_index < NUM_SERVOS) {
      if (code_seen('S'))
        MOVE_SERVO(servo_index, code_value_int());
      else {
        SERIAL_ECHO_START;
        SERIAL_ECHOPAIR(" Servo ", servo_index);
        SERIAL_ECHOLNPAIR(": ", servo[servo_index].read());
      }
    }
    else {
      SERIAL_ERROR_START;
      SERIAL_ECHOPAIR("Servo ", servo_index);
      SERIAL_ECHOLNPGM(" out of range");
    }
  }

#endif // HAS_SERVOS

#if HAS_BUZZER

  /**
   * M300: Play beep sound S<frequency Hz> P<duration ms>
   */
  inline void gcode_M300() {
    uint16_t const frequency = code_seen('S') ? code_value_ushort() : 260;
    uint16_t duration = code_seen('P') ? code_value_ushort() : 1000;

    // Limits the tone duration to 0-5 seconds.
    NOMORE(duration, 5000);

    BUZZ(duration, frequency);
  }

#endif // HAS_BUZZER

#if ENABLED(PIDTEMP)

  /**
   * M301: Set PID parameters P I D (and optionally C, L)
   *
   *   P[float] Kp term
   *   I[float] Ki term (unscaled)
   *   D[float] Kd term (unscaled)
   *
   * With PID_EXTRUSION_SCALING:
   *
   *   C[float] Kc term
   *   L[float] LPQ length
   */
  inline void gcode_M301() {

    // multi-extruder PID patch: M301 updates or prints a single extruder's PID values
    // default behaviour (omitting E parameter) is to update for extruder 0 only
    int e = code_seen('E') ? code_value_int() : 0; // extruder being updated

    if (e < HOTENDS) { // catch bad input value
      if (code_seen('P')) PID_PARAM(Kp, e) = code_value_float();
      if (code_seen('I')) PID_PARAM(Ki, e) = scalePID_i(code_value_float());
      if (code_seen('D')) PID_PARAM(Kd, e) = scalePID_d(code_value_float());
      #if ENABLED(PID_EXTRUSION_SCALING)
        if (code_seen('C')) PID_PARAM(Kc, e) = code_value_float();
        if (code_seen('L')) lpq_len = code_value_float();
        NOMORE(lpq_len, LPQ_MAX_LEN);
      #endif

      thermalManager.updatePID();
      SERIAL_ECHO_START;
      #if ENABLED(PID_PARAMS_PER_HOTEND)
        SERIAL_ECHOPAIR(" e:", e); // specify extruder in serial output
      #endif // PID_PARAMS_PER_HOTEND
      SERIAL_ECHOPAIR(" p:", PID_PARAM(Kp, e));
      SERIAL_ECHOPAIR(" i:", unscalePID_i(PID_PARAM(Ki, e)));
      SERIAL_ECHOPAIR(" d:", unscalePID_d(PID_PARAM(Kd, e)));
      #if ENABLED(PID_EXTRUSION_SCALING)
        //Kc does not have scaling applied above, or in resetting defaults
        SERIAL_ECHOPAIR(" c:", PID_PARAM(Kc, e));
      #endif
      SERIAL_EOL;
    }
    else {
      SERIAL_ERROR_START;
      SERIAL_ERRORLN(MSG_INVALID_EXTRUDER);
    }
  }

#endif // PIDTEMP

#if ENABLED(PIDTEMPBED)

  inline void gcode_M304() {
    if (code_seen('P')) thermalManager.bedKp = code_value_float();
    if (code_seen('I')) thermalManager.bedKi = scalePID_i(code_value_float());
    if (code_seen('D')) thermalManager.bedKd = scalePID_d(code_value_float());

    thermalManager.updatePID();

    SERIAL_ECHO_START;
    SERIAL_ECHOPAIR(" p:", thermalManager.bedKp);
    SERIAL_ECHOPAIR(" i:", unscalePID_i(thermalManager.bedKi));
    SERIAL_ECHOLNPAIR(" d:", unscalePID_d(thermalManager.bedKd));
  }

#endif // PIDTEMPBED

#if defined(CHDK) || HAS_PHOTOGRAPH

  /**
   * M240: Trigger a camera by emulating a Canon RC-1
   *       See http://www.doc-diy.net/photo/rc-1_hacked/
   */
  inline void gcode_M240() {
    #ifdef CHDK

      OUT_WRITE(CHDK, HIGH);
      chdkHigh = millis();
      chdkActive = true;

    #elif HAS_PHOTOGRAPH

      const uint8_t NUM_PULSES = 16;
      const float PULSE_LENGTH = 0.01524;
      for (int i = 0; i < NUM_PULSES; i++) {
        WRITE(PHOTOGRAPH_PIN, HIGH);
        _delay_ms(PULSE_LENGTH);
        WRITE(PHOTOGRAPH_PIN, LOW);
        _delay_ms(PULSE_LENGTH);
      }
      delay(7.33);
      for (int i = 0; i < NUM_PULSES; i++) {
        WRITE(PHOTOGRAPH_PIN, HIGH);
        _delay_ms(PULSE_LENGTH);
        WRITE(PHOTOGRAPH_PIN, LOW);
        _delay_ms(PULSE_LENGTH);
      }

    #endif // !CHDK && HAS_PHOTOGRAPH
  }

#endif // CHDK || PHOTOGRAPH_PIN

#if HAS_LCD_CONTRAST

  /**
   * M250: Read and optionally set the LCD contrast
   */
  inline void gcode_M250() {
    if (code_seen('C')) set_lcd_contrast(code_value_int());
    SERIAL_PROTOCOLPGM("lcd contrast value: ");
    SERIAL_PROTOCOL(lcd_contrast);
    SERIAL_EOL;
  }

#endif // HAS_LCD_CONTRAST

#if ENABLED(PREVENT_COLD_EXTRUSION)

  /**
   * M302: Allow cold extrudes, or set the minimum extrude temperature
   *
   *       S<temperature> sets the minimum extrude temperature
   *       P<bool> enables (1) or disables (0) cold extrusion
   *
   *  Examples:
   *
   *       M302         ; report current cold extrusion state
   *       M302 P0      ; enable cold extrusion checking
   *       M302 P1      ; disables cold extrusion checking
   *       M302 S0      ; always allow extrusion (disables checking)
   *       M302 S170    ; only allow extrusion above 170
   *       M302 S170 P1 ; set min extrude temp to 170 but leave disabled
   */
  inline void gcode_M302() {
    bool seen_S = code_seen('S');
    if (seen_S) {
      thermalManager.extrude_min_temp = code_value_temp_abs();
      thermalManager.allow_cold_extrude = (thermalManager.extrude_min_temp == 0);
    }

    if (code_seen('P'))
      thermalManager.allow_cold_extrude = (thermalManager.extrude_min_temp == 0) || code_value_bool();
    else if (!seen_S) {
      // Report current state
      SERIAL_ECHO_START;
      SERIAL_ECHOPAIR("Cold extrudes are ", (thermalManager.allow_cold_extrude ? "en" : "dis"));
      SERIAL_ECHOPAIR("abled (min temp ", int(thermalManager.extrude_min_temp + 0.5));
      SERIAL_ECHOLNPGM("C)");
    }
  }

#endif // PREVENT_COLD_EXTRUSION

/**
 * M303: PID relay autotune
 *
 *       S<temperature> sets the target temperature. (default 150C)
 *       E<extruder> (-1 for the bed) (default 0)
 *       C<cycles>
 *       U<bool> with a non-zero value will apply the result to current settings
 */
inline void gcode_M303() {
  #if HAS_PID_HEATING
    int e = code_seen('E') ? code_value_int() : 0;
    int c = code_seen('C') ? code_value_int() : 5;
    bool u = code_seen('U') && code_value_bool();

    float temp = code_seen('S') ? code_value_temp_abs() : (e < 0 ? 70.0 : 150.0);

    if (e >= 0 && e < HOTENDS)
      target_extruder = e;

    KEEPALIVE_STATE(NOT_BUSY); // don't send "busy: processing" messages during autotune output

    thermalManager.PID_autotune(temp, e, c, u);

    KEEPALIVE_STATE(IN_HANDLER);
  #else
    SERIAL_ERROR_START;
    SERIAL_ERRORLNPGM(MSG_ERR_M303_DISABLED);
  #endif
}

#if ENABLED(MORGAN_SCARA)

  bool SCARA_move_to_cal(uint8_t delta_a, uint8_t delta_b) {
    if (IsRunning()) {
      forward_kinematics_SCARA(delta_a, delta_b);
      destination[X_AXIS] = LOGICAL_X_POSITION(cartes[X_AXIS]);
      destination[Y_AXIS] = LOGICAL_Y_POSITION(cartes[Y_AXIS]);
      destination[Z_AXIS] = current_position[Z_AXIS];
      prepare_move_to_destination();
      return true;
    }
    return false;
  }

  /**
   * M360: SCARA calibration: Move to cal-position ThetaA (0 deg calibration)
   */
  inline bool gcode_M360() {
    SERIAL_ECHOLNPGM(" Cal: Theta 0");
    return SCARA_move_to_cal(0, 120);
  }

  /**
   * M361: SCARA calibration: Move to cal-position ThetaB (90 deg calibration - steps per degree)
   */
  inline bool gcode_M361() {
    SERIAL_ECHOLNPGM(" Cal: Theta 90");
    return SCARA_move_to_cal(90, 130);
  }

  /**
   * M362: SCARA calibration: Move to cal-position PsiA (0 deg calibration)
   */
  inline bool gcode_M362() {
    SERIAL_ECHOLNPGM(" Cal: Psi 0");
    return SCARA_move_to_cal(60, 180);
  }

  /**
   * M363: SCARA calibration: Move to cal-position PsiB (90 deg calibration - steps per degree)
   */
  inline bool gcode_M363() {
    SERIAL_ECHOLNPGM(" Cal: Psi 90");
    return SCARA_move_to_cal(50, 90);
  }

  /**
   * M364: SCARA calibration: Move to cal-position PSIC (90 deg to Theta calibration position)
   */
  inline bool gcode_M364() {
    SERIAL_ECHOLNPGM(" Cal: Theta-Psi 90");
    return SCARA_move_to_cal(45, 135);
  }

#endif // SCARA

#if ENABLED(EXT_SOLENOID)

  void enable_solenoid(uint8_t num) {
    switch (num) {
      case 0:
        OUT_WRITE(SOL0_PIN, HIGH);
        break;
        #if HAS_SOLENOID_1
          case 1:
            OUT_WRITE(SOL1_PIN, HIGH);
            break;
        #endif
        #if HAS_SOLENOID_2
          case 2:
            OUT_WRITE(SOL2_PIN, HIGH);
            break;
        #endif
        #if HAS_SOLENOID_3
          case 3:
            OUT_WRITE(SOL3_PIN, HIGH);
            break;
        #endif
      default:
        SERIAL_ECHO_START;
        SERIAL_ECHOLNPGM(MSG_INVALID_SOLENOID);
        break;
    }
  }

  void enable_solenoid_on_active_extruder() { enable_solenoid(active_extruder); }

  void disable_all_solenoids() {
    OUT_WRITE(SOL0_PIN, LOW);
    OUT_WRITE(SOL1_PIN, LOW);
    OUT_WRITE(SOL2_PIN, LOW);
    OUT_WRITE(SOL3_PIN, LOW);
  }

  /**
   * M380: Enable solenoid on the active extruder
   */
  inline void gcode_M380() { enable_solenoid_on_active_extruder(); }

  /**
   * M381: Disable all solenoids
   */
  inline void gcode_M381() { disable_all_solenoids(); }

#endif // EXT_SOLENOID

/**
 * M400: Finish all moves
 */
inline void gcode_M400() { stepper.synchronize(); }

#if HAS_BED_PROBE

  /**
   * M401: Engage Z Servo endstop if available
   */
  inline void gcode_M401() { DEPLOY_PROBE(); }

  /**
   * M402: Retract Z Servo endstop if enabled
   */
  inline void gcode_M402() { STOW_PROBE(); }

#endif // HAS_BED_PROBE

#if ENABLED(FILAMENT_WIDTH_SENSOR)

  /**
   * M404: Display or set (in current units) the nominal filament width (3mm, 1.75mm ) W<3.0>
   */
  inline void gcode_M404() {
    if (code_seen('W')) {
      filament_width_nominal = code_value_linear_units();
    }
    else {
      SERIAL_PROTOCOLPGM("Filament dia (nominal mm):");
      SERIAL_PROTOCOLLN(filament_width_nominal);
    }
  }

  /**
   * M405: Turn on filament sensor for control
   */
  inline void gcode_M405() {
    // This is technically a linear measurement, but since it's quantized to centimeters and is a different unit than
    // everything else, it uses code_value_int() instead of code_value_linear_units().
    if (code_seen('D')) meas_delay_cm = code_value_int();
    NOMORE(meas_delay_cm, MAX_MEASUREMENT_DELAY);

    if (filwidth_delay_index[1] == -1) { // Initialize the ring buffer if not done since startup
      int temp_ratio = thermalManager.widthFil_to_size_ratio();

      for (uint8_t i = 0; i < COUNT(measurement_delay); ++i)
        measurement_delay[i] = temp_ratio - 100;  // Subtract 100 to scale within a signed byte

      filwidth_delay_index[0] = filwidth_delay_index[1] = 0;
    }

    filament_sensor = true;

    //SERIAL_PROTOCOLPGM("Filament dia (measured mm):");
    //SERIAL_PROTOCOL(filament_width_meas);
    //SERIAL_PROTOCOLPGM("Extrusion ratio(%):");
    //SERIAL_PROTOCOL(flow_percentage[active_extruder]);
  }

  /**
   * M406: Turn off filament sensor for control
   */
  inline void gcode_M406() { filament_sensor = false; }

  /**
   * M407: Get measured filament diameter on serial output
   */
  inline void gcode_M407() {
    SERIAL_PROTOCOLPGM("Filament dia (measured mm):");
    SERIAL_PROTOCOLLN(filament_width_meas);
  }

#endif // FILAMENT_WIDTH_SENSOR

void quickstop_stepper() {
  stepper.quick_stop();
  stepper.synchronize();
  set_current_from_steppers_for_axis(ALL_AXES);
  SYNC_PLAN_POSITION_KINEMATIC();
}

#if PLANNER_LEVELING
  /**
   * M420: Enable/Disable Bed Leveling
   */
  inline void gcode_M420() { if (code_seen('S')) set_bed_leveling_enabled(code_value_bool()); }
#endif

#if ENABLED(MESH_BED_LEVELING)

  /**
   * M421: Set a single Mesh Bed Leveling Z coordinate
   * Use either 'M421 X<linear> Y<linear> Z<linear>' or 'M421 I<xindex> J<yindex> Z<linear>'
   */
  inline void gcode_M421() {
    int8_t px = 0, py = 0;
    float z = 0;
    bool hasX, hasY, hasZ, hasI, hasJ;
    if ((hasX = code_seen('X'))) px = mbl.probe_index_x(code_value_axis_units(X_AXIS));
    if ((hasY = code_seen('Y'))) py = mbl.probe_index_y(code_value_axis_units(Y_AXIS));
    if ((hasI = code_seen('I'))) px = code_value_axis_units(X_AXIS);
    if ((hasJ = code_seen('J'))) py = code_value_axis_units(Y_AXIS);
    if ((hasZ = code_seen('Z'))) z = code_value_axis_units(Z_AXIS);

    if (hasX && hasY && hasZ) {

      if (px >= 0 && py >= 0)
        mbl.set_z(px, py, z);
      else {
        SERIAL_ERROR_START;
        SERIAL_ERRORLNPGM(MSG_ERR_MESH_XY);
      }
    }
    else if (hasI && hasJ && hasZ) {
      if (px >= 0 && px < MESH_NUM_X_POINTS && py >= 0 && py < MESH_NUM_Y_POINTS)
        mbl.set_z(px, py, z);
      else {
        SERIAL_ERROR_START;
        SERIAL_ERRORLNPGM(MSG_ERR_MESH_XY);
      }
    }
    else {
      SERIAL_ERROR_START;
      SERIAL_ERRORLNPGM(MSG_ERR_M421_PARAMETERS);
    }
  }

#endif

/**
 * M428: Set home_offset based on the distance between the
 *       current_position and the nearest "reference point."
 *       If an axis is past center its endstop position
 *       is the reference-point. Otherwise it uses 0. This allows
 *       the Z offset to be set near the bed when using a max endstop.
 *
 *       M428 can't be used more than 2cm away from 0 or an endstop.
 *
 *       Use M206 to set these values directly.
 */
inline void gcode_M428() {
  bool err = false;
  LOOP_XYZ(i) {
    if (axis_homed[i]) {
      float base = (current_position[i] > (soft_endstop_min[i] + soft_endstop_max[i]) * 0.5) ? base_home_pos(i) : 0,
            diff = current_position[i] - LOGICAL_POSITION(base, i);
      if (diff > -20 && diff < 20) {
        set_home_offset((AxisEnum)i, home_offset[i] - diff);
      }
      else {
        SERIAL_ERROR_START;
        SERIAL_ERRORLNPGM(MSG_ERR_M428_TOO_FAR);
        LCD_ALERTMESSAGEPGM("Err: Too far!");
        BUZZ(200, 40);
        err = true;
        break;
      }
    }
  }

  if (!err) {
    SYNC_PLAN_POSITION_KINEMATIC();
    report_current_position();
    LCD_MESSAGEPGM(MSG_HOME_OFFSETS_APPLIED);
    BUZZ(200, 659);
    BUZZ(200, 698);
  }
}

/**
 * M500: Store settings in EEPROM
 */
inline void gcode_M500() {
  Config_StoreSettings();
}

/**
 * M501: Read settings from EEPROM
 */
inline void gcode_M501() {
  Config_RetrieveSettings();
}

/**
 * M502: Revert to default settings
 */
inline void gcode_M502() {
  Config_ResetDefault();
}

/**
 * M503: print settings currently in memory
 */
inline void gcode_M503() {
  Config_PrintSettings(code_seen('S') && !code_value_bool());
}

#if ENABLED(ABORT_ON_ENDSTOP_HIT_FEATURE_ENABLED)

  /**
   * M540: Set whether SD card print should abort on endstop hit (M540 S<0|1>)
   */
  inline void gcode_M540() {
    if (code_seen('S')) stepper.abort_on_endstop_hit = code_value_bool();
  }

#endif // ABORT_ON_ENDSTOP_HIT_FEATURE_ENABLED

#if HAS_BED_PROBE

  inline void gcode_M851() {

    SERIAL_ECHO_START;
    SERIAL_ECHOPGM(MSG_ZPROBE_ZOFFSET);
    SERIAL_CHAR(' ');

    if (code_seen('Z')) {
      float value = code_value_axis_units(Z_AXIS);
      if (Z_PROBE_OFFSET_RANGE_MIN <= value && value <= Z_PROBE_OFFSET_RANGE_MAX) {
        zprobe_zoffset = value;
        SERIAL_ECHO(zprobe_zoffset);
      }
      else {
        SERIAL_ECHOPAIR(MSG_Z_MIN, Z_PROBE_OFFSET_RANGE_MIN);
        SERIAL_CHAR(' ');
        SERIAL_ECHOPAIR(MSG_Z_MAX, Z_PROBE_OFFSET_RANGE_MAX);
      }
    }
    else {
      SERIAL_ECHOPAIR(": ", zprobe_zoffset);
    }

    SERIAL_EOL;
  }

#endif // HAS_BED_PROBE

#if ENABLED(FILAMENT_CHANGE_FEATURE)

  /**
   * M600: Pause for filament change
   *
   *  E[distance] - Retract the filament this far (negative value)
   *  Z[distance] - Move the Z axis by this distance
   *  X[position] - Move to this X position, with Y
   *  Y[position] - Move to this Y position, with X
   *  L[distance] - Retract distance for removal (manual reload)
   *
   *  Default values are used for omitted arguments.
   *
   */
  inline void gcode_M600() {

    if (thermalManager.tooColdToExtrude(active_extruder)) {
      SERIAL_ERROR_START;
      SERIAL_ERRORLNPGM(MSG_TOO_COLD_FOR_M600);
      return;
    }

    // Show initial message and wait for synchronize steppers
    lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_INIT);
    stepper.synchronize();

    float lastpos[NUM_AXIS];

    // Save current position of all axes
    LOOP_XYZE(i)
      lastpos[i] = destination[i] = current_position[i];

    // Define runplan for move axes
    #if IS_KINEMATIC
      #define RUNPLAN(RATE_MM_S) inverse_kinematics(destination); \
                                 planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], destination[E_AXIS], RATE_MM_S, active_extruder);
    #else
      #define RUNPLAN(RATE_MM_S) line_to_destination(RATE_MM_S);
    #endif

    KEEPALIVE_STATE(IN_HANDLER);

    // Initial retract before move to filament change position
    if (code_seen('E')) destination[E_AXIS] += code_value_axis_units(E_AXIS);
    #if defined(FILAMENT_CHANGE_RETRACT_LENGTH) && FILAMENT_CHANGE_RETRACT_LENGTH > 0
      else destination[E_AXIS] -= FILAMENT_CHANGE_RETRACT_LENGTH;
    #endif

    RUNPLAN(FILAMENT_CHANGE_RETRACT_FEEDRATE);

    // Lift Z axis
    float z_lift = code_seen('Z') ? code_value_axis_units(Z_AXIS) :
      #if defined(FILAMENT_CHANGE_Z_ADD) && FILAMENT_CHANGE_Z_ADD > 0
        FILAMENT_CHANGE_Z_ADD
      #else
        0
      #endif
    ;

    if (z_lift > 0) {
      destination[Z_AXIS] += z_lift;
      NOMORE(destination[Z_AXIS], Z_MAX_POS);
      RUNPLAN(FILAMENT_CHANGE_Z_FEEDRATE);
    }

    // Move XY axes to filament exchange position
    if (code_seen('X')) destination[X_AXIS] = code_value_axis_units(X_AXIS);
    #ifdef FILAMENT_CHANGE_X_POS
      else destination[X_AXIS] = FILAMENT_CHANGE_X_POS;
    #endif

    if (code_seen('Y')) destination[Y_AXIS] = code_value_axis_units(Y_AXIS);
    #ifdef FILAMENT_CHANGE_Y_POS
      else destination[Y_AXIS] = FILAMENT_CHANGE_Y_POS;
    #endif

    RUNPLAN(FILAMENT_CHANGE_XY_FEEDRATE);

    stepper.synchronize();
    lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_UNLOAD);

    // Unload filament
    if (code_seen('L')) destination[E_AXIS] += code_value_axis_units(E_AXIS);
    #if defined(FILAMENT_CHANGE_UNLOAD_LENGTH) && FILAMENT_CHANGE_UNLOAD_LENGTH > 0
      else destination[E_AXIS] -= FILAMENT_CHANGE_UNLOAD_LENGTH;
    #endif

    RUNPLAN(FILAMENT_CHANGE_UNLOAD_FEEDRATE);

    // Synchronize steppers and then disable extruders steppers for manual filament changing
    stepper.synchronize();
    disable_e0();
    disable_e1();
    disable_e2();
    disable_e3();
    delay(100);

    #if HAS_BUZZER
      millis_t next_tick = 0;
    #endif

    // Wait for filament insert by user and press button
    lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_INSERT);

    while (!lcd_clicked()) {
      #if HAS_BUZZER
        millis_t ms = millis();
        if (ms >= next_tick) {
          BUZZ(300, 2000);
          next_tick = ms + 2500; // Beep every 2.5s while waiting
        }
      #endif
      idle(true);
    }
    delay(100);
    while (lcd_clicked()) idle(true);
    delay(100);

    // Show load message
    lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_LOAD);

    // Load filament
    if (code_seen('L')) destination[E_AXIS] -= code_value_axis_units(E_AXIS);
    #if defined(FILAMENT_CHANGE_LOAD_LENGTH) && FILAMENT_CHANGE_LOAD_LENGTH > 0
      else destination[E_AXIS] += FILAMENT_CHANGE_LOAD_LENGTH;
    #endif

    RUNPLAN(FILAMENT_CHANGE_LOAD_FEEDRATE);
    stepper.synchronize();

    #if defined(FILAMENT_CHANGE_EXTRUDE_LENGTH) && FILAMENT_CHANGE_EXTRUDE_LENGTH > 0
      do {
        // Extrude filament to get into hotend
        lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_EXTRUDE);
        destination[E_AXIS] += FILAMENT_CHANGE_EXTRUDE_LENGTH;
        RUNPLAN(FILAMENT_CHANGE_EXTRUDE_FEEDRATE);
        stepper.synchronize();
        // Ask user if more filament should be extruded
        KEEPALIVE_STATE(PAUSED_FOR_USER);
        lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_OPTION);
        while (filament_change_menu_response == FILAMENT_CHANGE_RESPONSE_WAIT_FOR) idle(true);
        KEEPALIVE_STATE(IN_HANDLER);
      } while (filament_change_menu_response != FILAMENT_CHANGE_RESPONSE_RESUME_PRINT);
    #endif

    lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_RESUME);

    KEEPALIVE_STATE(IN_HANDLER);

    // Set extruder to saved position
    current_position[E_AXIS] = lastpos[E_AXIS];
    destination[E_AXIS] = lastpos[E_AXIS];
    planner.set_e_position_mm(current_position[E_AXIS]);

    #if IS_KINEMATIC
      // Move XYZ to starting position, then E
      inverse_kinematics(lastpos);
      planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], destination[E_AXIS], FILAMENT_CHANGE_XY_FEEDRATE, active_extruder);
      planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], lastpos[E_AXIS], FILAMENT_CHANGE_XY_FEEDRATE, active_extruder);
    #else
      // Move XY to starting position, then Z, then E
      destination[X_AXIS] = lastpos[X_AXIS];
      destination[Y_AXIS] = lastpos[Y_AXIS];
      RUNPLAN(FILAMENT_CHANGE_XY_FEEDRATE);
      destination[Z_AXIS] = lastpos[Z_AXIS];
      RUNPLAN(FILAMENT_CHANGE_Z_FEEDRATE);
    #endif
    stepper.synchronize();

    #if ENABLED(FILAMENT_RUNOUT_SENSOR)
      filament_ran_out = false;
    #endif

    // Show status screen
    lcd_filament_change_show_message(FILAMENT_CHANGE_MESSAGE_STATUS);
  }

#endif // FILAMENT_CHANGE_FEATURE

#if ENABLED(DUAL_X_CARRIAGE)

  /**
   * M605: Set dual x-carriage movement mode
   *
   *    M605 S0: Full control mode. The slicer has full control over x-carriage movement
   *    M605 S1: Auto-park mode. The inactive head will auto park/unpark without slicer involvement
   *    M605 S2 [Xnnn] [Rmmm]: Duplication mode. The second extruder will duplicate the first with nnn
   *                         units x-offset and an optional differential hotend temperature of
   *                         mmm degrees. E.g., with "M605 S2 X100 R2" the second extruder will duplicate
   *                         the first with a spacing of 100mm in the x direction and 2 degrees hotter.
   *
   *    Note: the X axis should be homed after changing dual x-carriage mode.
   */
  inline void gcode_M605() {
    stepper.synchronize();
    if (code_seen('S')) dual_x_carriage_mode = code_value_byte();
    switch (dual_x_carriage_mode) {
      case DXC_DUPLICATION_MODE:
        if (code_seen('X')) duplicate_extruder_x_offset = max(code_value_axis_units(X_AXIS), X2_MIN_POS - x_home_pos(0));
        if (code_seen('R')) duplicate_extruder_temp_offset = code_value_temp_diff();
        SERIAL_ECHO_START;
        SERIAL_ECHOPGM(MSG_HOTEND_OFFSET);
        SERIAL_CHAR(' ');
        SERIAL_ECHO(hotend_offset[X_AXIS][0]);
        SERIAL_CHAR(',');
        SERIAL_ECHO(hotend_offset[Y_AXIS][0]);
        SERIAL_CHAR(' ');
        SERIAL_ECHO(duplicate_extruder_x_offset);
        SERIAL_CHAR(',');
        SERIAL_ECHOLN(hotend_offset[Y_AXIS][1]);
        break;
      case DXC_FULL_CONTROL_MODE:
      case DXC_AUTO_PARK_MODE:
        break;
      default:
        dual_x_carriage_mode = DEFAULT_DUAL_X_CARRIAGE_MODE;
        break;
    }
    active_extruder_parked = false;
    extruder_duplication_enabled = false;
    delayed_move_time = 0;
  }

#elif ENABLED(DUAL_NOZZLE_DUPLICATION_MODE)

  inline void gcode_M605() {
    stepper.synchronize();
    extruder_duplication_enabled = code_seen('S') && code_value_int() == 2;
    SERIAL_ECHO_START;
    SERIAL_ECHOLNPAIR(MSG_DUPLICATION_MODE, extruder_duplication_enabled ? MSG_ON : MSG_OFF);
  }

#endif // M605

#if ENABLED(LIN_ADVANCE)
  /**
   * M905: Set advance factor
   */
  inline void gcode_M905() {
    stepper.synchronize();
    stepper.advance_M905(code_seen('K') ? code_value_float() : -1.0);
  }
#endif

/**
 * M907: Set digital trimpot motor current using axis codes X, Y, Z, E, B, S
 */
inline void gcode_M907() {
  #if HAS_DIGIPOTSS
    LOOP_XYZE(i)
    if (code_seen(axis_codes[i])) stepper.digipot_current(i, code_value_int());
    if (code_seen('B')) stepper.digipot_current(4, code_value_int());
    if (code_seen('S')) for (int i = 0; i <= 4; i++) stepper.digipot_current(i, code_value_int());
  #elif HAS_MOTOR_CURRENT_PWM
    #if PIN_EXISTS(MOTOR_CURRENT_PWM_XY)
      if (code_seen('X')) stepper.digipot_current(0, code_value_int());
    #endif
    #if PIN_EXISTS(MOTOR_CURRENT_PWM_Z)
      if (code_seen('Z')) stepper.digipot_current(1, code_value_int());
    #endif
    #if PIN_EXISTS(MOTOR_CURRENT_PWM_E)
      if (code_seen('E')) stepper.digipot_current(2, code_value_int());
    #endif
  #endif
  #if ENABLED(DIGIPOT_I2C)
    // this one uses actual amps in floating point
    LOOP_XYZE(i) if (code_seen(axis_codes[i])) digipot_i2c_set_current(i, code_value_float());
    // for each additional extruder (named B,C,D,E..., channels 4,5,6,7...)
    for (int i = NUM_AXIS; i < DIGIPOT_I2C_NUM_CHANNELS; i++) if (code_seen('B' + i - (NUM_AXIS))) digipot_i2c_set_current(i, code_value_float());
  #endif
  #if ENABLED(DAC_STEPPER_CURRENT)
    if (code_seen('S')) {
      float dac_percent = code_value_float();
      for (uint8_t i = 0; i <= 4; i++) dac_current_percent(i, dac_percent);
    }
    LOOP_XYZE(i) if (code_seen(axis_codes[i])) dac_current_percent(i, code_value_float());
  #endif
}

#if HAS_DIGIPOTSS || ENABLED(DAC_STEPPER_CURRENT)

  /**
   * M908: Control digital trimpot directly (M908 P<pin> S<current>)
   */
  inline void gcode_M908() {
    #if HAS_DIGIPOTSS
      stepper.digitalPotWrite(
        code_seen('P') ? code_value_int() : 0,
        code_seen('S') ? code_value_int() : 0
      );
    #endif
    #ifdef DAC_STEPPER_CURRENT
      dac_current_raw(
        code_seen('P') ? code_value_byte() : -1,
        code_seen('S') ? code_value_ushort() : 0
      );
    #endif
  }

  #if ENABLED(DAC_STEPPER_CURRENT) // As with Printrbot RevF

    inline void gcode_M909() { dac_print_values(); }

    inline void gcode_M910() { dac_commit_eeprom(); }

  #endif

#endif // HAS_DIGIPOTSS || DAC_STEPPER_CURRENT

#if HAS_MICROSTEPS

  // M350 Set microstepping mode. Warning: Steps per unit remains unchanged. S code sets stepping mode for all drivers.
  inline void gcode_M350() {
    if (code_seen('S')) for (int i = 0; i <= 4; i++) stepper.microstep_mode(i, code_value_byte());
    LOOP_XYZE(i) if (code_seen(axis_codes[i])) stepper.microstep_mode(i, code_value_byte());
    if (code_seen('B')) stepper.microstep_mode(4, code_value_byte());
    stepper.microstep_readings();
  }

  /**
   * M351: Toggle MS1 MS2 pins directly with axis codes X Y Z E B
   *       S# determines MS1 or MS2, X# sets the pin high/low.
   */
  inline void gcode_M351() {
    if (code_seen('S')) switch (code_value_byte()) {
      case 1:
        LOOP_XYZE(i) if (code_seen(axis_codes[i])) stepper.microstep_ms(i, code_value_byte(), -1);
        if (code_seen('B')) stepper.microstep_ms(4, code_value_byte(), -1);
        break;
      case 2:
        LOOP_XYZE(i) if (code_seen(axis_codes[i])) stepper.microstep_ms(i, -1, code_value_byte());
        if (code_seen('B')) stepper.microstep_ms(4, -1, code_value_byte());
        break;
    }
    stepper.microstep_readings();
  }

#endif // HAS_MICROSTEPS

#if ENABLED(MIXING_EXTRUDER)

  /**
   * M163: Set a single mix factor for a mixing extruder
   *       This is called "weight" by some systems.
   *
   *   S[index]   The channel index to set
   *   P[float]   The mix value
   *
   */
  inline void gcode_M163() {
    int mix_index = code_seen('S') ? code_value_int() : 0;
    float mix_value = code_seen('P') ? code_value_float() : 0.0;
    if (mix_index < MIXING_STEPPERS) mixing_factor[mix_index] = mix_value;
  }

  #if MIXING_VIRTUAL_TOOLS > 1

    /**
     * M164: Store the current mix factors as a virtual tool.
     *
     *   S[index]   The virtual tool to store
     *
     */
    inline void gcode_M164() {
      int tool_index = code_seen('S') ? code_value_int() : 0;
      if (tool_index < MIXING_VIRTUAL_TOOLS) {
        normalize_mix();
        for (uint8_t i = 0; i < MIXING_STEPPERS; i++)
          mixing_virtual_tool_mix[tool_index][i] = mixing_factor[i];
      }
    }

  #endif

  #if ENABLED(DIRECT_MIXING_IN_G1)
    /**
     * M165: Set multiple mix factors for a mixing extruder.
     *       Factors that are left out will be set to 0.
     *       All factors together must add up to 1.0.
     *
     *   A[factor] Mix factor for extruder stepper 1
     *   B[factor] Mix factor for extruder stepper 2
     *   C[factor] Mix factor for extruder stepper 3
     *   D[factor] Mix factor for extruder stepper 4
     *   H[factor] Mix factor for extruder stepper 5
     *   I[factor] Mix factor for extruder stepper 6
     *
     */
    inline void gcode_M165() { gcode_get_mix(); }
  #endif

#endif // MIXING_EXTRUDER

/**
 * M999: Restart after being stopped
 *
 * Default behaviour is to flush the serial buffer and request
 * a resend to the host starting on the last N line received.
 *
 * Sending "M999 S1" will resume printing without flushing the
 * existing command buffer.
 *
 */
inline void gcode_M999() {
  Running = true;
  lcd_reset_alert_level();

  if (code_seen('S') && code_value_bool()) return;

  // gcode_LastN = Stopped_gcode_LastN;
  FlushSerialRequestResend();
}

#if ENABLED(SWITCHING_EXTRUDER)
  inline void move_extruder_servo(uint8_t e) {
    const int angles[2] = SWITCHING_EXTRUDER_SERVO_ANGLES;
    MOVE_SERVO(SWITCHING_EXTRUDER_SERVO_NR, angles[e]);
  }
#endif

inline void invalid_extruder_error(const uint8_t &e) {
  SERIAL_ECHO_START;
  SERIAL_CHAR('T');
  SERIAL_PROTOCOL_F(e, DEC);
  SERIAL_ECHOLN(MSG_INVALID_EXTRUDER);
}

/**
 * Perform a tool-change, which may result in moving the
 * previous tool out of the way and the new tool into place.
 */
void tool_change(const uint8_t tmp_extruder, const float fr_mm_s/*=0.0*/, bool no_move/*=false*/) {
  #if ENABLED(MIXING_EXTRUDER) && MIXING_VIRTUAL_TOOLS > 1

    if (tmp_extruder >= MIXING_VIRTUAL_TOOLS) {
      invalid_extruder_error(tmp_extruder);
      return;
    }

    // T0-Tnnn: Switch virtual tool by changing the mix
    for (uint8_t j = 0; j < MIXING_STEPPERS; j++)
      mixing_factor[j] = mixing_virtual_tool_mix[tmp_extruder][j];

  #else //!MIXING_EXTRUDER || MIXING_VIRTUAL_TOOLS <= 1

    #if HOTENDS > 1

      if (tmp_extruder >= EXTRUDERS) {
        invalid_extruder_error(tmp_extruder);
        return;
      }

      float old_feedrate_mm_s = feedrate_mm_s;

      feedrate_mm_s = fr_mm_s > 0.0 ? (old_feedrate_mm_s = fr_mm_s) : XY_PROBE_FEEDRATE_MM_S;

      if (tmp_extruder != active_extruder) {
        if (!no_move && axis_unhomed_error(true, true, true)) {
          SERIAL_ECHOLNPGM("No move on toolchange");
          no_move = true;
        }

        // Save current position to destination, for use later
        set_destination_to_current();

        #if ENABLED(DUAL_X_CARRIAGE)

          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) {
              SERIAL_ECHOPGM("Dual X Carriage Mode ");
              switch (dual_x_carriage_mode) {
                case DXC_DUPLICATION_MODE: SERIAL_ECHOLNPGM("DXC_DUPLICATION_MODE"); break;
                case DXC_AUTO_PARK_MODE: SERIAL_ECHOLNPGM("DXC_AUTO_PARK_MODE"); break;
                case DXC_FULL_CONTROL_MODE: SERIAL_ECHOLNPGM("DXC_FULL_CONTROL_MODE"); break;
              }
            }
          #endif

          if (dual_x_carriage_mode == DXC_AUTO_PARK_MODE && IsRunning() &&
              (delayed_move_time || current_position[X_AXIS] != x_home_pos(active_extruder))
          ) {
            #if ENABLED(DEBUG_LEVELING_FEATURE)
              if (DEBUGGING(LEVELING)) {
                SERIAL_ECHOPAIR("Raise to ", current_position[Z_AXIS] + TOOLCHANGE_PARK_ZLIFT); SERIAL_EOL;
                SERIAL_ECHOPAIR("MoveX to ", x_home_pos(active_extruder)); SERIAL_EOL;
                SERIAL_ECHOPAIR("Lower to ", current_position[Z_AXIS]); SERIAL_EOL;
              }
            #endif
            // Park old head: 1) raise 2) move to park position 3) lower
            for (uint8_t i = 0; i < 3; i++)
              planner.buffer_line(
                i == 0 ? current_position[X_AXIS] : x_home_pos(active_extruder),
                current_position[Y_AXIS],
                current_position[Z_AXIS] + (i == 2 ? 0 : TOOLCHANGE_PARK_ZLIFT),
                current_position[E_AXIS],
                planner.max_feedrate_mm_s[i == 1 ? X_AXIS : Z_AXIS],
                active_extruder
              );
            stepper.synchronize();
          }

          // apply Y & Z extruder offset (x offset is already used in determining home pos)
          current_position[Y_AXIS] -= hotend_offset[Y_AXIS][active_extruder] - hotend_offset[Y_AXIS][tmp_extruder];
          current_position[Z_AXIS] -= hotend_offset[Z_AXIS][active_extruder] - hotend_offset[Z_AXIS][tmp_extruder];
          active_extruder = tmp_extruder;

          // This function resets the max/min values - the current position may be overwritten below.
          set_axis_is_at_home(X_AXIS);

          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) DEBUG_POS("New Extruder", current_position);
          #endif

          switch (dual_x_carriage_mode) {
            case DXC_FULL_CONTROL_MODE:
              current_position[X_AXIS] = LOGICAL_X_POSITION(inactive_extruder_x_pos);
              inactive_extruder_x_pos = RAW_X_POSITION(destination[X_AXIS]);
              break;
            case DXC_DUPLICATION_MODE:
              active_extruder_parked = (active_extruder == 0); // this triggers the second extruder to move into the duplication position
              if (active_extruder_parked)
                current_position[X_AXIS] = LOGICAL_X_POSITION(inactive_extruder_x_pos);
              else
                current_position[X_AXIS] = destination[X_AXIS] + duplicate_extruder_x_offset;
              inactive_extruder_x_pos = RAW_X_POSITION(destination[X_AXIS]);
              extruder_duplication_enabled = false;
              break;
            default:
              // record raised toolhead position for use by unpark
              memcpy(raised_parked_position, current_position, sizeof(raised_parked_position));
              raised_parked_position[Z_AXIS] += TOOLCHANGE_UNPARK_ZLIFT;
              active_extruder_parked = true;
              delayed_move_time = 0;
              break;
          }

          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) {
              SERIAL_ECHOLNPAIR("Active extruder parked: ", active_extruder_parked ? "yes" : "no");
              DEBUG_POS("New extruder (parked)", current_position);
            }
          #endif

          // No extra case for HAS_ABL in DUAL_X_CARRIAGE. Does that mean they don't work together?
        #else // !DUAL_X_CARRIAGE

          #if ENABLED(SWITCHING_EXTRUDER)
            // <0 if the new nozzle is higher, >0 if lower. A bigger raise when lower.
            float z_diff = hotend_offset[Z_AXIS][active_extruder] - hotend_offset[Z_AXIS][tmp_extruder],
                  z_raise = 0.3 + (z_diff > 0.0 ? z_diff : 0.0);

            // Always raise by some amount
            planner.buffer_line(
              current_position[X_AXIS],
              current_position[Y_AXIS],
              current_position[Z_AXIS] + z_raise,
              current_position[E_AXIS],
              planner.max_feedrate_mm_s[Z_AXIS],
              active_extruder
            );
            stepper.synchronize();

            move_extruder_servo(active_extruder);
            delay(500);

            // Move back down, if needed
            if (z_raise != z_diff) {
              planner.buffer_line(
                current_position[X_AXIS],
                current_position[Y_AXIS],
                current_position[Z_AXIS] + z_diff,
                current_position[E_AXIS],
                planner.max_feedrate_mm_s[Z_AXIS],
                active_extruder
              );
              stepper.synchronize();
            }
          #endif

          /**
           * Set current_position to the position of the new nozzle.
           * Offsets are based on linear distance, so we need to get
           * the resulting position in coordinate space.
           *
           * - With grid or 3-point leveling, offset XYZ by a tilted vector
           * - With mesh leveling, update Z for the new position
           * - Otherwise, just use the raw linear distance
           *
           * Software endstops are altered here too. Consider a case where:
           *   E0 at X=0 ... E1 at X=10
           * When we switch to E1 now X=10, but E1 can't move left.
           * To express this we apply the change in XY to the software endstops.
           * E1 can move farther right than E0, so the right limit is extended.
           *
           * Note that we don't adjust the Z software endstops. Why not?
           * Consider a case where Z=0 (here) and switching to E1 makes Z=1
           * because the bed is 1mm lower at the new position. As long as
           * the first nozzle is out of the way, the carriage should be
           * allowed to move 1mm lower. This technically "breaks" the
           * Z software endstop. But this is technically correct (and
           * there is no viable alternative).
           */
          #if ABL_PLANAR
            // Offset extruder, make sure to apply the bed level rotation matrix
            vector_3 tmp_offset_vec = vector_3(hotend_offset[X_AXIS][tmp_extruder],
                                               hotend_offset[Y_AXIS][tmp_extruder],
                                               0),
                     act_offset_vec = vector_3(hotend_offset[X_AXIS][active_extruder],
                                               hotend_offset[Y_AXIS][active_extruder],
                                               0),
                     offset_vec = tmp_offset_vec - act_offset_vec;

            #if ENABLED(DEBUG_LEVELING_FEATURE)
              if (DEBUGGING(LEVELING)) {
                tmp_offset_vec.debug("tmp_offset_vec");
                act_offset_vec.debug("act_offset_vec");
                offset_vec.debug("offset_vec (BEFORE)");
              }
            #endif

            offset_vec.apply_rotation(planner.bed_level_matrix.transpose(planner.bed_level_matrix));

            #if ENABLED(DEBUG_LEVELING_FEATURE)
              if (DEBUGGING(LEVELING)) offset_vec.debug("offset_vec (AFTER)");
            #endif

            // Adjustments to the current position
            float xydiff[2] = { offset_vec.x, offset_vec.y };
            current_position[Z_AXIS] += offset_vec.z;

          #else // !ABL_PLANAR

            float xydiff[2] = {
              hotend_offset[X_AXIS][tmp_extruder] - hotend_offset[X_AXIS][active_extruder],
              hotend_offset[Y_AXIS][tmp_extruder] - hotend_offset[Y_AXIS][active_extruder]
            };

            #if ENABLED(MESH_BED_LEVELING)

              if (mbl.active()) {
                #if ENABLED(DEBUG_LEVELING_FEATURE)
                  if (DEBUGGING(LEVELING)) SERIAL_ECHOPAIR("Z before MBL: ", current_position[Z_AXIS]);
                #endif
                float xpos = RAW_CURRENT_POSITION(X_AXIS),
                      ypos = RAW_CURRENT_POSITION(Y_AXIS);
                current_position[Z_AXIS] += mbl.get_z(xpos + xydiff[X_AXIS], ypos + xydiff[Y_AXIS]) - mbl.get_z(xpos, ypos);
                #if ENABLED(DEBUG_LEVELING_FEATURE)
                  if (DEBUGGING(LEVELING))
                    SERIAL_ECHOLNPAIR(" after: ", current_position[Z_AXIS]);
                #endif
              }

            #endif // MESH_BED_LEVELING

          #endif // !HAS_ABL

          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) {
              SERIAL_ECHOPAIR("Offset Tool XY by { ", xydiff[X_AXIS]);
              SERIAL_ECHOPAIR(", ", xydiff[Y_AXIS]);
              SERIAL_ECHOLNPGM(" }");
            }
          #endif

          // The newly-selected extruder XY is actually at...
          current_position[X_AXIS] += xydiff[X_AXIS];
          current_position[Y_AXIS] += xydiff[Y_AXIS];
          for (uint8_t i = X_AXIS; i <= Y_AXIS; i++) {
            position_shift[i] += xydiff[i];
            update_software_endstops((AxisEnum)i);
          }

          // Set the new active extruder
          active_extruder = tmp_extruder;

        #endif // !DUAL_X_CARRIAGE

        #if ENABLED(DEBUG_LEVELING_FEATURE)
          if (DEBUGGING(LEVELING)) DEBUG_POS("Sync After Toolchange", current_position);
        #endif

        // Tell the planner the new "current position"
        SYNC_PLAN_POSITION_KINEMATIC();

        // Move to the "old position" (move the extruder into place)
        if (!no_move && IsRunning()) {
          #if ENABLED(DEBUG_LEVELING_FEATURE)
            if (DEBUGGING(LEVELING)) DEBUG_POS("Move back", destination);
          #endif
          prepare_move_to_destination();
        }

      } // (tmp_extruder != active_extruder)

      stepper.synchronize();

      #if ENABLED(EXT_SOLENOID)
        disable_all_solenoids();
        enable_solenoid_on_active_extruder();
      #endif // EXT_SOLENOID

      feedrate_mm_s = old_feedrate_mm_s;

    #else // HOTENDS <= 1

      // Set the new active extruder
      active_extruder = tmp_extruder;

      UNUSED(fr_mm_s);
      UNUSED(no_move);

    #endif // HOTENDS <= 1

    SERIAL_ECHO_START;
    SERIAL_ECHOLNPAIR(MSG_ACTIVE_EXTRUDER, (int)active_extruder);

  #endif //!MIXING_EXTRUDER || MIXING_VIRTUAL_TOOLS <= 1
}

/**
 * T0-T3: Switch tool, usually switching extruders
 *
 *   F[units/min] Set the movement feedrate
 *   S1           Don't move the tool in XY after change
 */
inline void gcode_T(uint8_t tmp_extruder) {

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      SERIAL_ECHOPAIR(">>> gcode_T(", tmp_extruder);
      SERIAL_ECHOLNPGM(")");
      DEBUG_POS("BEFORE", current_position);
    }
  #endif

  #if HOTENDS == 1 || (ENABLED(MIXING_EXTRUDER) && MIXING_VIRTUAL_TOOLS > 1)

    tool_change(tmp_extruder);

  #elif HOTENDS > 1

    tool_change(
      tmp_extruder,
      code_seen('F') ? MMM_TO_MMS(code_value_axis_units(X_AXIS)) : 0.0,
      (tmp_extruder == active_extruder) || (code_seen('S') && code_value_bool())
    );

  #endif

  #if ENABLED(DEBUG_LEVELING_FEATURE)
    if (DEBUGGING(LEVELING)) {
      DEBUG_POS("AFTER", current_position);
      SERIAL_ECHOLNPGM("<<< gcode_T");
    }
  #endif
}

/**
 * Process a single command and dispatch it to its handler
 * This is called from the main loop()
 */
void process_next_command() {
  current_command = command_queue[cmd_queue_index_r];

  if (DEBUGGING(ECHO)) {
    SERIAL_ECHO_START;
    SERIAL_ECHOLN(current_command);
  }

  // Sanitize the current command:
  //  - Skip leading spaces
  //  - Bypass N[-0-9][0-9]*[ ]*
  //  - Overwrite * with nul to mark the end
  while (*current_command == ' ') ++current_command;
  if (*current_command == 'N' && NUMERIC_SIGNED(current_command[1])) {
    current_command += 2; // skip N[-0-9]
    while (NUMERIC(*current_command)) ++current_command; // skip [0-9]*
    while (*current_command == ' ') ++current_command; // skip [ ]*
  }
  char* starpos = strchr(current_command, '*');  // * should always be the last parameter
  if (starpos) while (*starpos == ' ' || *starpos == '*') *starpos-- = '\0'; // nullify '*' and ' '

  char *cmd_ptr = current_command;

  // Get the command code, which must be G, M, or T
  char command_code = *cmd_ptr++;

  // Skip spaces to get the numeric part
  while (*cmd_ptr == ' ') cmd_ptr++;

  uint16_t codenum = 0; // define ahead of goto

  // Bail early if there's no code
  bool code_is_good = NUMERIC(*cmd_ptr);
  if (!code_is_good) goto ExitUnknownCommand;

#ifdef G38_2_3
  double codenum_float;
  codenum_float = atof(cmd_ptr);  //allow for decimal point in command
#endif

  // Get and skip the code number
  do {
    codenum = (codenum * 10) + (*cmd_ptr - '0');
    cmd_ptr++;
  } while (NUMERIC(*cmd_ptr));

  // Skip all spaces to get to the first argument, or nul
  while (*cmd_ptr == ' ') cmd_ptr++;

  // The command's arguments (if any) start here, for sure!
  current_command_args = cmd_ptr;

  KEEPALIVE_STATE(IN_HANDLER);

  // Handle a known G, M, or T
  switch (command_code) {
    case 'G': switch (codenum) {

      // G0, G1
      case 0:
      case 1:
        #if IS_SCARA
          gcode_G0_G1(codenum == 0);
        #else
          gcode_G0_G1();
        #endif
        break;

      // G2, G3
      #if ENABLED(ARC_SUPPORT) && DISABLED(SCARA)
        case 2: // G2  - CW ARC
        case 3: // G3  - CCW ARC
          gcode_G2_G3(codenum == 2);
          break;
      #endif

      // G4 Dwell
      case 4:
        gcode_G4();
        break;

      #if ENABLED(BEZIER_CURVE_SUPPORT)
        // G5
        case 5: // G5  - Cubic B_spline
          gcode_G5();
          break;
      #endif // BEZIER_CURVE_SUPPORT

      #if ENABLED(FWRETRACT)
        case 10: // G10: retract
        case 11: // G11: retract_recover
          gcode_G10_G11(codenum == 10);
          break;
      #endif // FWRETRACT

      #if ENABLED(NOZZLE_CLEAN_FEATURE)
        case 12:
          gcode_G12(); // G12: Nozzle Clean
          break;
      #endif // NOZZLE_CLEAN_FEATURE

      #if ENABLED(INCH_MODE_SUPPORT)
        case 20: //G20: Inch Mode
          gcode_G20();
          break;

        case 21: //G21: MM Mode
          gcode_G21();
          break;
      #endif // INCH_MODE_SUPPORT

      #if ENABLED(NOZZLE_PARK_FEATURE)
        case 27: // G27: Nozzle Park
          gcode_G27();
          break;
      #endif // NOZZLE_PARK_FEATURE

      case 28: // G28: Home all axes, one at a time
        gcode_G28();
        break;

      #if PLANNER_LEVELING
        case 29: // G29 Detailed Z probe, probes the bed at 3 or more points.
          gcode_G29();
          break;
      #endif // PLANNER_LEVELING

      #if HAS_BED_PROBE

        case 30: // G30 Single Z probe
          gcode_G30();
          break;

        #if ENABLED(Z_PROBE_SLED)

            case 31: // G31: dock the sled
              gcode_G31();
              break;

            case 32: // G32: undock the sled
              gcode_G32();
              break;

        #endif // Z_PROBE_SLED
      #endif // HAS_BED_PROBE

      #ifdef G38_2_3
	   case 38:  //G38.2 & G38.3
	     gcode_G38(codenum_float);
          break;
	 #endif
 
      case 90: // G90
        relative_mode = false;
        break;
      case 91: // G91
        relative_mode = true;
        break;

      case 92: // G92
        gcode_G92();
        break;
    }
    break;

    case 'M': switch (codenum) {
      #if ENABLED(ULTIPANEL) || ENABLED(EMERGENCY_PARSER)
        case 0: // M0 - Unconditional stop - Wait for user button press on LCD
        case 1: // M1 - Conditional stop - Wait for user button press on LCD
          gcode_M0_M1();
          break;
      #endif // ULTIPANEL

      case 17:
        gcode_M17();
        break;

      #if ENABLED(SDSUPPORT)
        case 20: // M20 - list SD card
          gcode_M20(); break;
        case 21: // M21 - init SD card
          gcode_M21(); break;
        case 22: //M22 - release SD card
          gcode_M22(); break;
        case 23: //M23 - Select file
          gcode_M23(); break;
        case 24: //M24 - Start SD print
          gcode_M24(); break;
        case 25: //M25 - Pause SD print
          gcode_M25(); break;
        case 26: //M26 - Set SD index
          gcode_M26(); break;
        case 27: //M27 - Get SD status
          gcode_M27(); break;
        case 28: //M28 - Start SD write
          gcode_M28(); break;
        case 29: //M29 - Stop SD write
          gcode_M29(); break;
        case 30: //M30 <filename> Delete File
          gcode_M30(); break;
        case 32: //M32 - Select file and start SD print
          gcode_M32(); break;

        #if ENABLED(LONG_FILENAME_HOST_SUPPORT)
          case 33: //M33 - Get the long full path to a file or folder
            gcode_M33(); break;
        #endif // LONG_FILENAME_HOST_SUPPORT

        case 928: //M928 - Start SD write
          gcode_M928(); break;
      #endif //SDSUPPORT

      case 31: //M31 take time since the start of the SD print or an M109 command
        gcode_M31();
        break;

      case 42: //M42 -Change pin status via gcode
        gcode_M42();
        break;

      #if ENABLED(Z_MIN_PROBE_REPEATABILITY_TEST)
        case 48: // M48 Z probe repeatability
          gcode_M48();
          break;
      #endif // Z_MIN_PROBE_REPEATABILITY_TEST

      case 75: // Start print timer
        gcode_M75();
        break;

      case 76: // Pause print timer
        gcode_M76();
        break;

      case 77: // Stop print timer
        gcode_M77();
        break;

      #if ENABLED(PRINTCOUNTER)
        case 78: // Show print statistics
          gcode_M78();
          break;
      #endif

      #if ENABLED(M100_FREE_MEMORY_WATCHER)
        case 100:
          gcode_M100();
          break;
      #endif

      case 104: // M104
        gcode_M104();
        break;

      case 110: // M110: Set Current Line Number
        gcode_M110();
        break;

      case 111: // M111: Set debug level
        gcode_M111();
        break;

      #if DISABLED(EMERGENCY_PARSER)

        case 108: // M108: Cancel Waiting
          gcode_M108();
          break;

        case 112: // M112: Emergency Stop
          gcode_M112();
          break;

        case 410: // M410 quickstop - Abort all the planned moves.
          gcode_M410();
          break;

      #endif

      #if ENABLED(HOST_KEEPALIVE_FEATURE)
        case 113: // M113: Set Host Keepalive interval
          gcode_M113();
          break;
      #endif

      case 140: // M140: Set bed temp
        gcode_M140();
        break;

      case 105: // M105: Read current temperature
        gcode_M105();
        KEEPALIVE_STATE(NOT_BUSY);
        return; // "ok" already printed

      case 109: // M109: Wait for temperature
        gcode_M109();
        break;

      #if HAS_TEMP_BED
        case 190: // M190: Wait for bed heater to reach target
          gcode_M190();
          break;
      #endif // HAS_TEMP_BED

      #if FAN_COUNT > 0
        case 106: // M106: Fan On
          gcode_M106();
          break;
        case 107: // M107: Fan Off
          gcode_M107();
          break;
      #endif // FAN_COUNT > 0

      #if ENABLED(BARICUDA)
        // PWM for HEATER_1_PIN
        #if HAS_HEATER_1
          case 126: // M126: valve open
            gcode_M126();
            break;
          case 127: // M127: valve closed
            gcode_M127();
            break;
        #endif // HAS_HEATER_1

        // PWM for HEATER_2_PIN
        #if HAS_HEATER_2
          case 128: // M128: valve open
            gcode_M128();
            break;
          case 129: // M129: valve closed
            gcode_M129();
            break;
        #endif // HAS_HEATER_2
      #endif // BARICUDA

      #if HAS_POWER_SWITCH

        case 80: // M80: Turn on Power Supply
          gcode_M80();
          break;

      #endif // HAS_POWER_SWITCH

      case 81: // M81: Turn off Power, including Power Supply, if possible
        gcode_M81();
        break;

      case 82:
        gcode_M82();
        break;
      case 83:
        gcode_M83();
        break;
      case 18: // (for compatibility)
      case 84: // M84
        gcode_M18_M84();
        break;
      case 85: // M85
        gcode_M85();
        break;
      case 92: // M92: Set the steps-per-unit for one or more axes
        gcode_M92();
        break;
      case 115: // M115: Report capabilities
        gcode_M115();
        break;
      case 117: // M117: Set LCD message text, if possible
        gcode_M117();
        break;
      case 114: // M114: Report current position
        gcode_M114();
        break;
      case 120: // M120: Enable endstops
        gcode_M120();
        break;
      case 121: // M121: Disable endstops
        gcode_M121();
        break;
      case 119: // M119: Report endstop states
        gcode_M119();
        break;

      #if ENABLED(ULTIPANEL)

        case 145: // M145: Set material heatup parameters
          gcode_M145();
          break;

      #endif

      #if ENABLED(TEMPERATURE_UNITS_SUPPORT)
        case 149:
          gcode_M149();
          break;
      #endif

      #if ENABLED(BLINKM)

        case 150: // M150
          gcode_M150();
          break;

      #endif //BLINKM

      #if ENABLED(EXPERIMENTAL_I2CBUS)

        case 155:
          gcode_M155();
          break;

        case 156:
          gcode_M156();
          break;

      #endif //EXPERIMENTAL_I2CBUS

      #if ENABLED(MIXING_EXTRUDER)
        case 163: // M163 S<int> P<float> set weight for a mixing extruder
          gcode_M163();
          break;
        #if MIXING_VIRTUAL_TOOLS > 1
          case 164: // M164 S<int> save current mix as a virtual extruder
            gcode_M164();
            break;
        #endif
        #if ENABLED(DIRECT_MIXING_IN_G1)
          case 165: // M165 [ABCDHI]<float> set multiple mix weights
            gcode_M165();
            break;
        #endif
      #endif

      case 200: // M200 D<diameter> Set filament diameter and set E axis units to cubic. (Use S0 to revert to linear units.)
        gcode_M200();
        break;
      case 201: // M201
        gcode_M201();
        break;
      #if 0 // Not used for Sprinter/grbl gen6
        case 202: // M202
          gcode_M202();
          break;
      #endif
      case 203: // M203 max feedrate units/sec
        gcode_M203();
        break;
      case 204: // M204 acclereration S normal moves T filmanent only moves
        gcode_M204();
        break;
      case 205: //M205 advanced settings:  minimum travel speed S=while printing T=travel only,  B=minimum segment time X= maximum xy jerk, Z=maximum Z jerk
        gcode_M205();
        break;
      case 206: // M206 additional homing offset
        gcode_M206();
        break;

      #if ENABLED(DELTA)
        case 665: // M665 set delta configurations L<diagonal_rod> R<delta_radius> S<segments_per_sec>
          gcode_M665();
          break;
      #endif

      #if ENABLED(DELTA) || ENABLED(Z_DUAL_ENDSTOPS)
        case 666: // M666 set delta / dual endstop adjustment
          gcode_M666();
          break;
      #endif

      #if ENABLED(FWRETRACT)
        case 207: // M207 - Set Retract Length: S<length>, Feedrate: F<units/min>, and Z lift: Z<distance>
          gcode_M207();
          break;
        case 208: // M208 - Set Recover (unretract) Additional (!) Length: S<length> and Feedrate: F<units/min>
          gcode_M208();
          break;
        case 209: // M209 - Turn Automatic Retract Detection on/off: S<bool> (For slicers that don't support G10/11). Every normal extrude-only move will be classified as retract depending on the direction.
          gcode_M209();
          break;
      #endif // FWRETRACT

      case 211: // M211 - Enable, Disable, and/or Report software endstops
        gcode_M211();
        break;

      #if HOTENDS > 1
        case 218: // M218 - Set a tool offset: T<index> X<offset> Y<offset>
          gcode_M218();
          break;
      #endif

      case 220: // M220 - Set Feedrate Percentage: S<percent> ("FR" on your LCD)
        gcode_M220();
        break;

      case 221: // M221 - Set Flow Percentage: S<percent>
        gcode_M221();
        break;

      case 226: // M226 P<pin number> S<pin state>- Wait until the specified pin reaches the state required
        gcode_M226();
        break;

      #if HAS_SERVOS
        case 280: // M280 - set servo position absolute. P: servo index, S: angle or microseconds
          gcode_M280();
          break;
      #endif // HAS_SERVOS

      #if HAS_BUZZER
        case 300: // M300 - Play beep tone
          gcode_M300();
          break;
      #endif // HAS_BUZZER

      #if ENABLED(PIDTEMP)
        case 301: // M301
          gcode_M301();
          break;
      #endif // PIDTEMP

      #if ENABLED(PIDTEMPBED)
        case 304: // M304
          gcode_M304();
          break;
      #endif // PIDTEMPBED

      #if defined(CHDK) || HAS_PHOTOGRAPH
        case 240: // M240  Triggers a camera by emulating a Canon RC-1 : http://www.doc-diy.net/photo/rc-1_hacked/
          gcode_M240();
          break;
      #endif // CHDK || PHOTOGRAPH_PIN

      #if HAS_LCD_CONTRAST
        case 250: // M250  Set LCD contrast value: C<value> (value 0..63)
          gcode_M250();
          break;
      #endif // HAS_LCD_CONTRAST

      #if ENABLED(PREVENT_COLD_EXTRUSION)
        case 302: // allow cold extrudes, or set the minimum extrude temperature
          gcode_M302();
          break;
      #endif // PREVENT_COLD_EXTRUSION

      case 303: // M303 PID autotune
        gcode_M303();
        break;

      #if ENABLED(MORGAN_SCARA)
        case 360:  // M360 SCARA Theta pos1
          if (gcode_M360()) return;
          break;
        case 361:  // M361 SCARA Theta pos2
          if (gcode_M361()) return;
          break;
        case 362:  // M362 SCARA Psi pos1
          if (gcode_M362()) return;
          break;
        case 363:  // M363 SCARA Psi pos2
          if (gcode_M363()) return;
          break;
        case 364:  // M364 SCARA Psi pos3 (90 deg to Theta)
          if (gcode_M364()) return;
          break;
      #endif // SCARA

      case 400: // M400 finish all moves
        gcode_M400();
        break;

      #if HAS_BED_PROBE
        case 401:
          gcode_M401();
          break;
        case 402:
          gcode_M402();
          break;
      #endif // HAS_BED_PROBE

      #if ENABLED(FILAMENT_WIDTH_SENSOR)
        case 404:  //M404 Enter the nominal filament width (3mm, 1.75mm ) N<3.0> or display nominal filament width
          gcode_M404();
          break;
        case 405:  //M405 Turn on filament sensor for control
          gcode_M405();
          break;
        case 406:  //M406 Turn off filament sensor for control
          gcode_M406();
          break;
        case 407:   //M407 Display measured filament diameter
          gcode_M407();
          break;
      #endif // ENABLED(FILAMENT_WIDTH_SENSOR)

      #if ENABLED(MESH_BED_LEVELING)
        case 420: // M420 Enable/Disable Mesh Bed Leveling
          gcode_M420();
          break;
        case 421: // M421 Set a Mesh Bed Leveling Z coordinate
          gcode_M421();
          break;
      #endif

      case 428: // M428 Apply current_position to home_offset
        gcode_M428();
        break;

      case 500: // M500 Store settings in EEPROM
        gcode_M500();
        break;
      case 501: // M501 Read settings from EEPROM
        gcode_M501();
        break;
      case 502: // M502 Revert to default settings
        gcode_M502();
        break;
      case 503: // M503 print settings currently in memory
        gcode_M503();
        break;

      #if ENABLED(ABORT_ON_ENDSTOP_HIT_FEATURE_ENABLED)
        case 540:
          gcode_M540();
          break;
      #endif

      #if HAS_BED_PROBE
        case 851: // Set Z Probe Z Offset
          gcode_M851();
          break;
      #endif // HAS_BED_PROBE

      #if ENABLED(FILAMENT_CHANGE_FEATURE)
        case 600: //Pause for filament change X[pos] Y[pos] Z[relative lift] E[initial retract] L[later retract distance for removal]
          gcode_M600();
          break;
      #endif // FILAMENT_CHANGE_FEATURE

      #if ENABLED(DUAL_X_CARRIAGE)
        case 605:
          gcode_M605();
          break;
      #endif // DUAL_X_CARRIAGE

      #if ENABLED(LIN_ADVANCE)
        case 905: // M905 Set advance factor.
          gcode_M905();
          break;
      #endif

      case 907: // M907 Set digital trimpot motor current using axis codes.
        gcode_M907();
        break;

      #if HAS_DIGIPOTSS || ENABLED(DAC_STEPPER_CURRENT)

        case 908: // M908 Control digital trimpot directly.
          gcode_M908();
          break;

        #if ENABLED(DAC_STEPPER_CURRENT) // As with Printrbot RevF

          case 909: // M909 Print digipot/DAC current value
            gcode_M909();
            break;

          case 910: // M910 Commit digipot/DAC value to external EEPROM
            gcode_M910();
            break;

        #endif

      #endif // HAS_DIGIPOTSS || DAC_STEPPER_CURRENT

      #if HAS_MICROSTEPS

        case 350: // M350 Set microstepping mode. Warning: Steps per unit remains unchanged. S code sets stepping mode for all drivers.
          gcode_M350();
          break;

        case 351: // M351 Toggle MS1 MS2 pins directly, S# determines MS1 or MS2, X# sets the pin high/low.
          gcode_M351();
          break;

      #endif // HAS_MICROSTEPS

      case 999: // M999: Restart after being Stopped
        gcode_M999();
        break;
    }
    break;

    case 'T':
      gcode_T(codenum);
      break;

    default: code_is_good = false;
  }

  KEEPALIVE_STATE(NOT_BUSY);

ExitUnknownCommand:

  // Still unknown command? Throw an error
  if (!code_is_good) unknown_command_error();

  ok_to_send();
}

/**
 * Send a "Resend: nnn" message to the host to
 * indicate that a command needs to be re-sent.
 */
void FlushSerialRequestResend() {
  //char command_queue[cmd_queue_index_r][100]="Resend:";
  MYSERIAL.flush();
  SERIAL_PROTOCOLPGM(MSG_RESEND);
  SERIAL_PROTOCOLLN(gcode_LastN + 1);
  ok_to_send();
}

/**
 * Send an "ok" message to the host, indicating
 * that a command was successfully processed.
 *
 * If ADVANCED_OK is enabled also include:
 *   N<int>  Line number of the command, if any
 *   P<int>  Planner space remaining
 *   B<int>  Block queue space remaining
 */
void ok_to_send() {
  refresh_cmd_timeout();
  if (!send_ok[cmd_queue_index_r]) return;
  SERIAL_PROTOCOLPGM(MSG_OK);
  #if ENABLED(ADVANCED_OK)
    char* p = command_queue[cmd_queue_index_r];
    if (*p == 'N') {
      SERIAL_PROTOCOL(' ');
      SERIAL_ECHO(*p++);
      while (NUMERIC_SIGNED(*p))
        SERIAL_ECHO(*p++);
    }
    SERIAL_PROTOCOLPGM(" P"); SERIAL_PROTOCOL(int(BLOCK_BUFFER_SIZE - planner.movesplanned() - 1));
    SERIAL_PROTOCOLPGM(" B"); SERIAL_PROTOCOL(BUFSIZE - commands_in_queue);
  #endif
  SERIAL_EOL;
}

#if ENABLED(min_software_endstops) || ENABLED(max_software_endstops)

  /**
   * Constrain the given coordinates to the software endstops.
   */
  void clamp_to_software_endstops(float target[XYZ]) {
    #if ENABLED(min_software_endstops)
      NOLESS(target[X_AXIS], soft_endstop_min[X_AXIS]);
      NOLESS(target[Y_AXIS], soft_endstop_min[Y_AXIS]);
      NOLESS(target[Z_AXIS], soft_endstop_min[Z_AXIS]);
    #endif
    #if ENABLED(max_software_endstops)
      NOMORE(target[X_AXIS], soft_endstop_max[X_AXIS]);
      NOMORE(target[Y_AXIS], soft_endstop_max[Y_AXIS]);
      NOMORE(target[Z_AXIS], soft_endstop_max[Z_AXIS]);
    #endif
  }

#endif

#if ENABLED(AUTO_BED_LEVELING_BILINEAR)

  // Get the Z adjustment for non-linear bed leveling
  float bilinear_z_offset(float cartesian[XYZ]) {

    // XY relative to the probed area
    const float x = RAW_X_POSITION(cartesian[X_AXIS]) - bilinear_start[X_AXIS],
                y = RAW_Y_POSITION(cartesian[Y_AXIS]) - bilinear_start[Y_AXIS];

    // Convert to grid box units
    float ratio_x = x / bilinear_grid_spacing[X_AXIS],
          ratio_y = y / bilinear_grid_spacing[Y_AXIS];

    // Whole unit is the grid box index
    const int gridx = constrain(floor(ratio_x), 0, ABL_GRID_POINTS_X - 2),
              gridy = constrain(floor(ratio_y), 0, ABL_GRID_POINTS_Y - 2),
              nextx = gridx + (x < PROBE_BED_WIDTH ? 1 : 0),
              nexty = gridy + (y < PROBE_BED_HEIGHT ? 1 : 0);

    // Subtract whole to get the ratio within the grid box
    ratio_x = constrain(ratio_x - gridx, 0.0, 1.0);
    ratio_y = constrain(ratio_y - gridy, 0.0, 1.0);

    // Z at the box corners
    const float z1 = bed_level_grid[gridx][gridy],  // left-front
                z2 = bed_level_grid[gridx][nexty],  // left-back
                z3 = bed_level_grid[nextx][gridy],  // right-front
                z4 = bed_level_grid[nextx][nexty],  // right-back

                // Bilinear interpolate
                L = z1 + (z2 - z1) * ratio_y,   // Linear interp. LF -> LB
                R = z3 + (z4 - z3) * ratio_y,   // Linear interp. RF -> RB
                offset = L + ratio_x * (R - L);

    /*
    static float last_offset = 0;
    if (fabs(last_offset - offset) > 0.2) {
      SERIAL_ECHOPGM("Sudden Shift at ");
      SERIAL_ECHOPAIR("x=", x);
      SERIAL_ECHOPAIR(" / ", bilinear_grid_spacing[X_AXIS]);
      SERIAL_ECHOLNPAIR(" -> gridx=", gridx);
      SERIAL_ECHOPAIR(" y=", y);
      SERIAL_ECHOPAIR(" / ", bilinear_grid_spacing[Y_AXIS]);
      SERIAL_ECHOLNPAIR(" -> gridy=", gridy);
      SERIAL_ECHOPAIR(" ratio_x=", ratio_x);
      SERIAL_ECHOLNPAIR(" ratio_y=", ratio_y);
      SERIAL_ECHOPAIR(" z1=", z1);
      SERIAL_ECHOPAIR(" z2=", z2);
      SERIAL_ECHOPAIR(" z3=", z3);
      SERIAL_ECHOLNPAIR(" z4=", z4);
      SERIAL_ECHOPAIR(" L=", L);
      SERIAL_ECHOPAIR(" R=", R);
      SERIAL_ECHOLNPAIR(" offset=", offset);
    }
    last_offset = offset;
    //*/

    return offset;
  }

#endif // AUTO_BED_LEVELING_BILINEAR

#if ENABLED(DELTA)

  /**
   * Recalculate factors used for delta kinematics whenever
   * settings have been changed (e.g., by M665).
   */
  void recalc_delta_settings(float radius, float diagonal_rod) {
    delta_tower1_x = -SIN_60 * (radius + DELTA_RADIUS_TRIM_TOWER_1);  // front left tower
    delta_tower1_y = -COS_60 * (radius + DELTA_RADIUS_TRIM_TOWER_1);
    delta_tower2_x =  SIN_60 * (radius + DELTA_RADIUS_TRIM_TOWER_2);  // front right tower
    delta_tower2_y = -COS_60 * (radius + DELTA_RADIUS_TRIM_TOWER_2);
    delta_tower3_x = 0.0;                                             // back middle tower
    delta_tower3_y = (radius + DELTA_RADIUS_TRIM_TOWER_3);
    delta_diagonal_rod_2_tower_1 = sq(diagonal_rod + delta_diagonal_rod_trim_tower_1);
    delta_diagonal_rod_2_tower_2 = sq(diagonal_rod + delta_diagonal_rod_trim_tower_2);
    delta_diagonal_rod_2_tower_3 = sq(diagonal_rod + delta_diagonal_rod_trim_tower_3);
  }

  #if ENABLED(DELTA_FAST_SQRT)
    /**
     * Fast inverse sqrt from Quake III Arena
     * See: https://en.wikipedia.org/wiki/Fast_inverse_square_root
     */
    float Q_rsqrt(float number) {
      long i;
      float x2, y;
      const float threehalfs = 1.5f;
      x2 = number * 0.5f;
      y  = number;
      i  = * ( long * ) &y;                       // evil floating point bit level hacking
      i  = 0x5f3759df - ( i >> 1 );               // what the f***?
      y  = * ( float * ) &i;
      y  = y * ( threehalfs - ( x2 * y * y ) );   // 1st iteration
      // y  = y * ( threehalfs - ( x2 * y * y ) );   // 2nd iteration, this can be removed
      return y;
    }

    #define _SQRT(n) (1.0f / Q_rsqrt(n))

  #else

    #define _SQRT(n) sqrt(n)

  #endif

  /**
   * Delta Inverse Kinematics
   *
   * Calculate the tower positions for a given logical
   * position, storing the result in the delta[] array.
   *
   * This is an expensive calculation, requiring 3 square
   * roots per segmented linear move, and strains the limits
   * of a Mega2560 with a Graphical Display.
   *
   * Suggested optimizations include:
   *
   * - Disable the home_offset (M206) and/or position_shift (G92)
   *   features to remove up to 12 float additions.
   *
   * - Use a fast-inverse-sqrt function and add the reciprocal.
   *   (see above)
   */

  // Macro to obtain the Z position of an individual tower
  #define DELTA_Z(T) raw[Z_AXIS] + _SQRT(    \
    delta_diagonal_rod_2_tower_##T - HYPOT2( \
        delta_tower##T##_x - raw[X_AXIS],    \
        delta_tower##T##_y - raw[Y_AXIS]     \
      )                                      \
    )

  #define DELTA_RAW_IK() do {   \
    delta[A_AXIS] = DELTA_Z(1); \
    delta[B_AXIS] = DELTA_Z(2); \
    delta[C_AXIS] = DELTA_Z(3); \
  } while(0)

  #define DELTA_LOGICAL_IK() do {      \
    const float raw[XYZ] = {           \
      RAW_X_POSITION(logical[X_AXIS]), \
      RAW_Y_POSITION(logical[Y_AXIS]), \
      RAW_Z_POSITION(logical[Z_AXIS])  \
    };                                 \
    DELTA_RAW_IK();                    \
  } while(0)

  #define DELTA_DEBUG() do { \
      SERIAL_ECHOPAIR("cartesian X:", raw[X_AXIS]); \
      SERIAL_ECHOPAIR(" Y:", raw[Y_AXIS]);          \
      SERIAL_ECHOLNPAIR(" Z:", raw[Z_AXIS]);        \
      SERIAL_ECHOPAIR("delta A:", delta[A_AXIS]);   \
      SERIAL_ECHOPAIR(" B:", delta[B_AXIS]);        \
      SERIAL_ECHOLNPAIR(" C:", delta[C_AXIS]);      \
    } while(0)

  void inverse_kinematics(const float logical[XYZ]) {
    DELTA_LOGICAL_IK();
    // DELTA_DEBUG();
  }

  /**
   * Calculate the highest Z position where the
   * effector has the full range of XY motion.
   */
  float delta_safe_distance_from_top() {
    float cartesian[XYZ] = {
      LOGICAL_X_POSITION(0),
      LOGICAL_Y_POSITION(0),
      LOGICAL_Z_POSITION(0)
    };
    inverse_kinematics(cartesian);
    float distance = delta[A_AXIS];
    cartesian[Y_AXIS] = LOGICAL_Y_POSITION(DELTA_PRINTABLE_RADIUS);
    inverse_kinematics(cartesian);
    return abs(distance - delta[A_AXIS]);
  }

  /**
   * Delta Forward Kinematics
   *
   * See the Wikipedia article "Trilateration"
   * https://en.wikipedia.org/wiki/Trilateration
   *
   * Establish a new coordinate system in the plane of the
   * three carriage points. This system has its origin at
   * tower1, with tower2 on the X axis. Tower3 is in the X-Y
   * plane with a Z component of zero.
   * We will define unit vectors in this coordinate system
   * in our original coordinate system. Then when we calculate
   * the Xnew, Ynew and Znew values, we can translate back into
   * the original system by moving along those unit vectors
   * by the corresponding values.
   *
   * Variable names matched to Marlin, c-version, and avoid the
   * use of any vector library.
   *
   * by Andreas Hardtung 2016-06-07
   * based on a Java function from "Delta Robot Kinematics V3"
   * by Steve Graves
   *
   * The result is stored in the cartes[] array.
   */
  void forward_kinematics_DELTA(float z1, float z2, float z3) {
    // Create a vector in old coordinates along x axis of new coordinate
    float p12[3] = { delta_tower2_x - delta_tower1_x, delta_tower2_y - delta_tower1_y, z2 - z1 };

    // Get the Magnitude of vector.
    float d = sqrt( sq(p12[0]) + sq(p12[1]) + sq(p12[2]) );

    // Create unit vector by dividing by magnitude.
    float ex[3] = { p12[0] / d, p12[1] / d, p12[2] / d };

    // Get the vector from the origin of the new system to the third point.
    float p13[3] = { delta_tower3_x - delta_tower1_x, delta_tower3_y - delta_tower1_y, z3 - z1 };

    // Use the dot product to find the component of this vector on the X axis.
    float i = ex[0] * p13[0] + ex[1] * p13[1] + ex[2] * p13[2];

    // Create a vector along the x axis that represents the x component of p13.
    float iex[3] = { ex[0] * i, ex[1] * i, ex[2] * i };

    // Subtract the X component from the original vector leaving only Y. We use the
    // variable that will be the unit vector after we scale it.
    float ey[3] = { p13[0] - iex[0], p13[1] - iex[1], p13[2] - iex[2] };

    // The magnitude of Y component
    float j = sqrt( sq(ey[0]) + sq(ey[1]) + sq(ey[2]) );

    // Convert to a unit vector
    ey[0] /= j; ey[1] /= j;  ey[2] /= j;

    // The cross product of the unit x and y is the unit z
    // float[] ez = vectorCrossProd(ex, ey);
    float ez[3] = {
      ex[1] * ey[2] - ex[2] * ey[1],
      ex[2] * ey[0] - ex[0] * ey[2],
      ex[0] * ey[1] - ex[1] * ey[0]
    };

    // We now have the d, i and j values defined in Wikipedia.
    // Plug them into the equations defined in Wikipedia for Xnew, Ynew and Znew
    float Xnew = (delta_diagonal_rod_2_tower_1 - delta_diagonal_rod_2_tower_2 + sq(d)) / (d * 2),
          Ynew = ((delta_diagonal_rod_2_tower_1 - delta_diagonal_rod_2_tower_3 + HYPOT2(i, j)) / 2 - i * Xnew) / j,
          Znew = sqrt(delta_diagonal_rod_2_tower_1 - HYPOT2(Xnew, Ynew));

    // Start from the origin of the old coordinates and add vectors in the
    // old coords that represent the Xnew, Ynew and Znew to find the point
    // in the old system.
    cartes[X_AXIS] = delta_tower1_x + ex[0] * Xnew + ey[0] * Ynew - ez[0] * Znew;
    cartes[Y_AXIS] = delta_tower1_y + ex[1] * Xnew + ey[1] * Ynew - ez[1] * Znew;
    cartes[Z_AXIS] =             z1 + ex[2] * Xnew + ey[2] * Ynew - ez[2] * Znew;
  };

  void forward_kinematics_DELTA(float point[ABC]) {
    forward_kinematics_DELTA(point[A_AXIS], point[B_AXIS], point[C_AXIS]);
  }

#endif // DELTA

/**
 * Get the stepper positions in the cartes[] array.
 * Forward kinematics are applied for DELTA and SCARA.
 *
 * The result is in the current coordinate space with
 * leveling applied. The coordinates need to be run through
 * unapply_leveling to obtain the "ideal" coordinates
 * suitable for current_position, etc.
 */
void get_cartesian_from_steppers() {
  #if ENABLED(DELTA)
    forward_kinematics_DELTA(
      stepper.get_axis_position_mm(A_AXIS),
      stepper.get_axis_position_mm(B_AXIS),
      stepper.get_axis_position_mm(C_AXIS)
    );
    cartes[X_AXIS] += LOGICAL_X_POSITION(0);
    cartes[Y_AXIS] += LOGICAL_Y_POSITION(0);
    cartes[Z_AXIS] += LOGICAL_Z_POSITION(0);
  #elif IS_SCARA
    forward_kinematics_SCARA(
      stepper.get_axis_position_degrees(A_AXIS),
      stepper.get_axis_position_degrees(B_AXIS)
    );
    cartes[X_AXIS] += LOGICAL_X_POSITION(0);
    cartes[Y_AXIS] += LOGICAL_Y_POSITION(0);
    cartes[Z_AXIS] = stepper.get_axis_position_mm(Z_AXIS);
  #else
    cartes[X_AXIS] = stepper.get_axis_position_mm(X_AXIS);
    cartes[Y_AXIS] = stepper.get_axis_position_mm(Y_AXIS);
    cartes[Z_AXIS] = stepper.get_axis_position_mm(Z_AXIS);
  #endif
}

/**
 * Set the current_position for an axis based on
 * the stepper positions, removing any leveling that
 * may have been applied.
 */
void set_current_from_steppers_for_axis(const AxisEnum axis) {
  get_cartesian_from_steppers();
  #if PLANNER_LEVELING
    planner.unapply_leveling(cartes);
  #endif
  if (axis == ALL_AXES)
    memcpy(current_position, cartes, sizeof(cartes));
  else
    current_position[axis] = cartes[axis];
}

#if ENABLED(MESH_BED_LEVELING)

  /**
   * Prepare a mesh-leveled linear move in a Cartesian setup,
   * splitting the move where it crosses mesh borders.
   */
  void mesh_line_to_destination(float fr_mm_s, uint8_t x_splits = 0xff, uint8_t y_splits = 0xff) {
    int cx1 = mbl.cell_index_x(RAW_CURRENT_POSITION(X_AXIS)),
        cy1 = mbl.cell_index_y(RAW_CURRENT_POSITION(Y_AXIS)),
        cx2 = mbl.cell_index_x(RAW_X_POSITION(destination[X_AXIS])),
        cy2 = mbl.cell_index_y(RAW_Y_POSITION(destination[Y_AXIS]));
    NOMORE(cx1, MESH_NUM_X_POINTS - 2);
    NOMORE(cy1, MESH_NUM_Y_POINTS - 2);
    NOMORE(cx2, MESH_NUM_X_POINTS - 2);
    NOMORE(cy2, MESH_NUM_Y_POINTS - 2);

    if (cx1 == cx2 && cy1 == cy2) {
      // Start and end on same mesh square
      line_to_destination(fr_mm_s);
      set_current_to_destination();
      return;
    }

    #define MBL_SEGMENT_END(A) (current_position[A ##_AXIS] + (destination[A ##_AXIS] - current_position[A ##_AXIS]) * normalized_dist)

    float normalized_dist, end[NUM_AXIS];

    // Split at the left/front border of the right/top square
    int8_t gcx = max(cx1, cx2), gcy = max(cy1, cy2);
    if (cx2 != cx1 && TEST(x_splits, gcx)) {
      memcpy(end, destination, sizeof(end));
      destination[X_AXIS] = LOGICAL_X_POSITION(mbl.get_probe_x(gcx));
      normalized_dist = (destination[X_AXIS] - current_position[X_AXIS]) / (end[X_AXIS] - current_position[X_AXIS]);
      destination[Y_AXIS] = MBL_SEGMENT_END(Y);
      CBI(x_splits, gcx);
    }
    else if (cy2 != cy1 && TEST(y_splits, gcy)) {
      memcpy(end, destination, sizeof(end));
      destination[Y_AXIS] = LOGICAL_Y_POSITION(mbl.get_probe_y(gcy));
      normalized_dist = (destination[Y_AXIS] - current_position[Y_AXIS]) / (end[Y_AXIS] - current_position[Y_AXIS]);
      destination[X_AXIS] = MBL_SEGMENT_END(X);
      CBI(y_splits, gcy);
    }
    else {
      // Already split on a border
      line_to_destination(fr_mm_s);
      set_current_to_destination();
      return;
    }

    destination[Z_AXIS] = MBL_SEGMENT_END(Z);
    destination[E_AXIS] = MBL_SEGMENT_END(E);

    // Do the split and look for more borders
    mesh_line_to_destination(fr_mm_s, x_splits, y_splits);

    // Restore destination from stack
    memcpy(destination, end, sizeof(end));
    mesh_line_to_destination(fr_mm_s, x_splits, y_splits);
  }

#endif // MESH_BED_LEVELING

#if IS_KINEMATIC

  /**
   * Prepare a linear move in a DELTA or SCARA setup.
   *
   * This calls planner.buffer_line several times, adding
   * small incremental moves for DELTA or SCARA.
   */
  inline bool prepare_kinematic_move_to(float ltarget[NUM_AXIS]) {

    // Get the top feedrate of the move in the XY plane
    float _feedrate_mm_s = MMS_SCALED(feedrate_mm_s);

    // If the move is only in Z/E don't split up the move
    if (ltarget[X_AXIS] == current_position[X_AXIS] && ltarget[Y_AXIS] == current_position[Y_AXIS]) {
      inverse_kinematics(ltarget);
      planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], ltarget[E_AXIS], _feedrate_mm_s, active_extruder);
      return true;
    }

    // Get the cartesian distances moved in XYZE
    float difference[NUM_AXIS];
    LOOP_XYZE(i) difference[i] = ltarget[i] - current_position[i];

    // Get the linear distance in XYZ
    float cartesian_mm = sqrt(sq(difference[X_AXIS]) + sq(difference[Y_AXIS]) + sq(difference[Z_AXIS]));

    // If the move is very short, check the E move distance
    if (UNEAR_ZERO(cartesian_mm)) cartesian_mm = abs(difference[E_AXIS]);

    // No E move either? Game over.
    if (UNEAR_ZERO(cartesian_mm)) return false;

    // Minimum number of seconds to move the given distance
    float seconds = cartesian_mm / _feedrate_mm_s;

    // The number of segments-per-second times the duration
    // gives the number of segments
    uint16_t segments = delta_segments_per_second * seconds;

    // For SCARA minimum segment size is 0.5mm
    #if IS_SCARA
      NOMORE(segments, cartesian_mm * 2);
    #endif

    // At least one segment is required
    NOLESS(segments, 1);

    // The approximate length of each segment
    float segment_distance[XYZE] = {
            difference[X_AXIS] / segments,
            difference[Y_AXIS] / segments,
            difference[Z_AXIS] / segments,
            difference[E_AXIS] / segments
          };

    // SERIAL_ECHOPAIR("mm=", cartesian_mm);
    // SERIAL_ECHOPAIR(" seconds=", seconds);
    // SERIAL_ECHOLNPAIR(" segments=", segments);

    // Drop one segment so the last move is to the exact target.
    // If there's only 1 segment, loops will be skipped entirely.
    --segments;

    // Using "raw" coordinates saves 6 float subtractions
    // per segment, saving valuable CPU cycles

    #if ENABLED(USE_RAW_KINEMATICS)

      // Get the raw current position as starting point
      float raw[XYZE] = {
        RAW_CURRENT_POSITION(X_AXIS),
        RAW_CURRENT_POSITION(Y_AXIS),
        RAW_CURRENT_POSITION(Z_AXIS),
        current_position[E_AXIS]
      };

      #define DELTA_VAR raw

      // Delta can inline its kinematics
      #if ENABLED(DELTA)
        #define DELTA_IK() DELTA_RAW_IK()
      #else
        #define DELTA_IK() inverse_kinematics(raw)
      #endif

    #else

      // Get the logical current position as starting point
      float logical[XYZE];
      memcpy(logical, current_position, sizeof(logical));

      #define DELTA_VAR logical

      // Delta can inline its kinematics
      #if ENABLED(DELTA)
        #define DELTA_IK() DELTA_LOGICAL_IK()
      #else
        #define DELTA_IK() inverse_kinematics(logical)
      #endif

    #endif

    #if ENABLED(USE_DELTA_IK_INTERPOLATION)

      // Only interpolate XYZ. Advance E normally.
      #define DELTA_NEXT(ADDEND) LOOP_XYZ(i) DELTA_VAR[i] += ADDEND;

      // Get the starting delta if interpolation is possible
      if (segments >= 2) DELTA_IK();

      // Loop using decrement
      for (uint16_t s = segments + 1; --s;) {
        // Are there at least 2 moves left?
        if (s >= 2) {
          // Save the previous delta for interpolation
          float prev_delta[ABC] = { delta[A_AXIS], delta[B_AXIS], delta[C_AXIS] };

          // Get the delta 2 segments ahead (rather than the next)
          DELTA_NEXT(segment_distance[i] + segment_distance[i]);

          // Advance E normally
          DELTA_VAR[E_AXIS] += segment_distance[E_AXIS];

          // Get the exact delta for the move after this
          DELTA_IK();

          // Move to the interpolated delta position first
          planner.buffer_line(
            (prev_delta[A_AXIS] + delta[A_AXIS]) * 0.5,
            (prev_delta[B_AXIS] + delta[B_AXIS]) * 0.5,
            (prev_delta[C_AXIS] + delta[C_AXIS]) * 0.5,
            DELTA_VAR[E_AXIS], _feedrate_mm_s, active_extruder
          );

          // Advance E once more for the next move
          DELTA_VAR[E_AXIS] += segment_distance[E_AXIS];

          // Do an extra decrement of the loop
          --s;
        }
        else {
          // Get the last segment delta. (Used when segments is odd)
          DELTA_NEXT(segment_distance[i]);
          DELTA_VAR[E_AXIS] += segment_distance[E_AXIS];
          DELTA_IK();
        }

        // Move to the non-interpolated position
        planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], DELTA_VAR[E_AXIS], _feedrate_mm_s, active_extruder);
      }

    #else

      #define DELTA_NEXT(ADDEND) LOOP_XYZE(i) DELTA_VAR[i] += ADDEND;

      // For non-interpolated delta calculate every segment
      for (uint16_t s = segments + 1; --s;) {
        DELTA_NEXT(segment_distance[i]);
        DELTA_IK();
        planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], DELTA_VAR[E_AXIS], _feedrate_mm_s, active_extruder);
      }

    #endif

    // Since segment_distance is only approximate,
    // the final move must be to the exact destination.
    inverse_kinematics(ltarget);
    planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], ltarget[E_AXIS], _feedrate_mm_s, active_extruder);
    return true;
  }

#else

  /**
   * Prepare a linear move in a Cartesian setup.
   * If Mesh Bed Leveling is enabled, perform a mesh move.
   */
  inline bool prepare_move_to_destination_cartesian() {
    // Do not use feedrate_percentage for E or Z only moves
    if (current_position[X_AXIS] == destination[X_AXIS] && current_position[Y_AXIS] == destination[Y_AXIS]) {
      line_to_destination();
    }
    else {
      #if ENABLED(MESH_BED_LEVELING)
        if (mbl.active()) {
          mesh_line_to_destination(MMS_SCALED(feedrate_mm_s));
          return false;
        }
        else
      #endif
          line_to_destination(MMS_SCALED(feedrate_mm_s));
    }
    return true;
  }

#endif // !IS_KINEMATIC

#if ENABLED(DUAL_X_CARRIAGE)

  /**
   * Prepare a linear move in a dual X axis setup
   */
  inline bool prepare_move_to_destination_dualx() {
    if (active_extruder_parked) {
      if (dual_x_carriage_mode == DXC_DUPLICATION_MODE && active_extruder == 0) {
        // move duplicate extruder into correct duplication position.
        planner.set_position_mm(
          LOGICAL_X_POSITION(inactive_extruder_x_pos),
          current_position[Y_AXIS],
          current_position[Z_AXIS],
          current_position[E_AXIS]
        );
        planner.buffer_line(current_position[X_AXIS] + duplicate_extruder_x_offset,
                         current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], planner.max_feedrate_mm_s[X_AXIS], 1);
        SYNC_PLAN_POSITION_KINEMATIC();
        stepper.synchronize();
        extruder_duplication_enabled = true;
        active_extruder_parked = false;
      }
      else if (dual_x_carriage_mode == DXC_AUTO_PARK_MODE) { // handle unparking of head
        if (current_position[E_AXIS] == destination[E_AXIS]) {
          // This is a travel move (with no extrusion)
          // Skip it, but keep track of the current position
          // (so it can be used as the start of the next non-travel move)
          if (delayed_move_time != 0xFFFFFFFFUL) {
            set_current_to_destination();
            NOLESS(raised_parked_position[Z_AXIS], destination[Z_AXIS]);
            delayed_move_time = millis();
            return false;
          }
        }
        delayed_move_time = 0;
        // unpark extruder: 1) raise, 2) move into starting XY position, 3) lower
        planner.buffer_line(raised_parked_position[X_AXIS], raised_parked_position[Y_AXIS], raised_parked_position[Z_AXIS], current_position[E_AXIS], planner.max_feedrate_mm_s[Z_AXIS], active_extruder);
        planner.buffer_line(current_position[X_AXIS], current_position[Y_AXIS], raised_parked_position[Z_AXIS], current_position[E_AXIS], PLANNER_XY_FEEDRATE(), active_extruder);
        planner.buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], planner.max_feedrate_mm_s[Z_AXIS], active_extruder);
        active_extruder_parked = false;
      }
    }
    return true;
  }

#endif // DUAL_X_CARRIAGE

/**
 * Prepare a single move and get ready for the next one
 *
 * This may result in several calls to planner.buffer_line to
 * do smaller moves for DELTA, SCARA, mesh moves, etc.
 */
void prepare_move_to_destination() {
  clamp_to_software_endstops(destination);
  refresh_cmd_timeout();

  #if ENABLED(PREVENT_COLD_EXTRUSION)

    if (!DEBUGGING(DRYRUN)) {
      if (destination[E_AXIS] != current_position[E_AXIS]) {
        if (thermalManager.tooColdToExtrude(active_extruder)) {
          current_position[E_AXIS] = destination[E_AXIS]; // Behave as if the move really took place, but ignore E part
          SERIAL_ECHO_START;
          SERIAL_ECHOLNPGM(MSG_ERR_COLD_EXTRUDE_STOP);
        }
        #if ENABLED(PREVENT_LENGTHY_EXTRUDE)
          if (labs(destination[E_AXIS] - current_position[E_AXIS]) > EXTRUDE_MAXLENGTH) {
            current_position[E_AXIS] = destination[E_AXIS]; // Behave as if the move really took place, but ignore E part
            SERIAL_ECHO_START;
            SERIAL_ECHOLNPGM(MSG_ERR_LONG_EXTRUDE_STOP);
          }
        #endif
      }
    }

  #endif

  #if IS_KINEMATIC
    if (!prepare_kinematic_move_to(destination)) return;
  #else
    #if ENABLED(DUAL_X_CARRIAGE)
      if (!prepare_move_to_destination_dualx()) return;
    #endif
    if (!prepare_move_to_destination_cartesian()) return;
  #endif

  set_current_to_destination();
}

#if ENABLED(ARC_SUPPORT)
  /**
   * Plan an arc in 2 dimensions
   *
   * The arc is approximated by generating many small linear segments.
   * The length of each segment is configured in MM_PER_ARC_SEGMENT (Default 1mm)
   * Arcs should only be made relatively large (over 5mm), as larger arcs with
   * larger segments will tend to be more efficient. Your slicer should have
   * options for G2/G3 arc generation. In future these options may be GCode tunable.
   */
  void plan_arc(
    float logical[NUM_AXIS], // Destination position
    float* offset,           // Center of rotation relative to current_position
    uint8_t clockwise        // Clockwise?
  ) {

    float radius = HYPOT(offset[X_AXIS], offset[Y_AXIS]),
          center_X = current_position[X_AXIS] + offset[X_AXIS],
          center_Y = current_position[Y_AXIS] + offset[Y_AXIS],
          linear_travel = logical[Z_AXIS] - current_position[Z_AXIS],
          extruder_travel = logical[E_AXIS] - current_position[E_AXIS],
          r_X = -offset[X_AXIS],  // Radius vector from center to current location
          r_Y = -offset[Y_AXIS],
          rt_X = logical[X_AXIS] - center_X,
          rt_Y = logical[Y_AXIS] - center_Y;

    // CCW angle of rotation between position and target from the circle center. Only one atan2() trig computation required.
    float angular_travel = atan2(r_X * rt_Y - r_Y * rt_X, r_X * rt_X + r_Y * rt_Y);
    if (angular_travel < 0) angular_travel += RADIANS(360);
    if (clockwise) angular_travel -= RADIANS(360);

    // Make a circle if the angular rotation is 0
    if (angular_travel == 0 && current_position[X_AXIS] == logical[X_AXIS] && current_position[Y_AXIS] == logical[Y_AXIS])
      angular_travel += RADIANS(360);

    float mm_of_travel = HYPOT(angular_travel * radius, fabs(linear_travel));
    if (mm_of_travel < 0.001) return;
    uint16_t segments = floor(mm_of_travel / (MM_PER_ARC_SEGMENT));
    if (segments == 0) segments = 1;

    float theta_per_segment = angular_travel / segments;
    float linear_per_segment = linear_travel / segments;
    float extruder_per_segment = extruder_travel / segments;

    /**
     * Vector rotation by transformation matrix: r is the original vector, r_T is the rotated vector,
     * and phi is the angle of rotation. Based on the solution approach by Jens Geisler.
     *     r_T = [cos(phi) -sin(phi);
     *            sin(phi)  cos(phi] * r ;
     *
     * For arc generation, the center of the circle is the axis of rotation and the radius vector is
     * defined from the circle center to the initial position. Each line segment is formed by successive
     * vector rotations. This requires only two cos() and sin() computations to form the rotation
     * matrix for the duration of the entire arc. Error may accumulate from numerical round-off, since
     * all double numbers are single precision on the Arduino. (True double precision will not have
     * round off issues for CNC applications.) Single precision error can accumulate to be greater than
     * tool precision in some cases. Therefore, arc path correction is implemented.
     *
     * Small angle approximation may be used to reduce computation overhead further. This approximation
     * holds for everything, but very small circles and large MM_PER_ARC_SEGMENT values. In other words,
     * theta_per_segment would need to be greater than 0.1 rad and N_ARC_CORRECTION would need to be large
     * to cause an appreciable drift error. N_ARC_CORRECTION~=25 is more than small enough to correct for
     * numerical drift error. N_ARC_CORRECTION may be on the order a hundred(s) before error becomes an
     * issue for CNC machines with the single precision Arduino calculations.
     *
     * This approximation also allows plan_arc to immediately insert a line segment into the planner
     * without the initial overhead of computing cos() or sin(). By the time the arc needs to be applied
     * a correction, the planner should have caught up to the lag caused by the initial plan_arc overhead.
     * This is important when there are successive arc motions.
     */
    // Vector rotation matrix values
    float cos_T = 1 - 0.5 * sq(theta_per_segment); // Small angle approximation
    float sin_T = theta_per_segment;

    float arc_target[NUM_AXIS];
    float sin_Ti, cos_Ti, r_new_Y;
    uint16_t i;
    int8_t count = 0;

    // Initialize the linear axis
    arc_target[Z_AXIS] = current_position[Z_AXIS];

    // Initialize the extruder axis
    arc_target[E_AXIS] = current_position[E_AXIS];

    float fr_mm_s = MMS_SCALED(feedrate_mm_s);

    millis_t next_idle_ms = millis() + 200UL;

    for (i = 1; i < segments; i++) { // Iterate (segments-1) times

      thermalManager.manage_heater();
      millis_t now = millis();
      if (ELAPSED(now, next_idle_ms)) {
        next_idle_ms = now + 200UL;
        idle();
      }

      if (++count < N_ARC_CORRECTION) {
        // Apply vector rotation matrix to previous r_X / 1
        r_new_Y = r_X * sin_T + r_Y * cos_T;
        r_X = r_X * cos_T - r_Y * sin_T;
        r_Y = r_new_Y;
      }
      else {
        // Arc correction to radius vector. Computed only every N_ARC_CORRECTION increments.
        // Compute exact location by applying transformation matrix from initial radius vector(=-offset).
        // To reduce stuttering, the sin and cos could be computed at different times.
        // For now, compute both at the same time.
        cos_Ti = cos(i * theta_per_segment);
        sin_Ti = sin(i * theta_per_segment);
        r_X = -offset[X_AXIS] * cos_Ti + offset[Y_AXIS] * sin_Ti;
        r_Y = -offset[X_AXIS] * sin_Ti - offset[Y_AXIS] * cos_Ti;
        count = 0;
      }

      // Update arc_target location
      arc_target[X_AXIS] = center_X + r_X;
      arc_target[Y_AXIS] = center_Y + r_Y;
      arc_target[Z_AXIS] += linear_per_segment;
      arc_target[E_AXIS] += extruder_per_segment;

      clamp_to_software_endstops(arc_target);

      #if IS_KINEMATIC
        inverse_kinematics(arc_target);
        planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], arc_target[E_AXIS], fr_mm_s, active_extruder);
      #else
        planner.buffer_line(arc_target[X_AXIS], arc_target[Y_AXIS], arc_target[Z_AXIS], arc_target[E_AXIS], fr_mm_s, active_extruder);
      #endif
    }

    // Ensure last segment arrives at target location.
    #if IS_KINEMATIC
      inverse_kinematics(logical);
      planner.buffer_line(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], logical[E_AXIS], fr_mm_s, active_extruder);
    #else
      planner.buffer_line(logical[X_AXIS], logical[Y_AXIS], logical[Z_AXIS], logical[E_AXIS], fr_mm_s, active_extruder);
    #endif

    // As far as the parser is concerned, the position is now == target. In reality the
    // motion control system might still be processing the action and the real tool position
    // in any intermediate location.
    set_current_to_destination();
  }
#endif

#if ENABLED(BEZIER_CURVE_SUPPORT)

  void plan_cubic_move(const float offset[4]) {
    cubic_b_spline(current_position, destination, offset, MMS_SCALED(feedrate_mm_s), active_extruder);

    // As far as the parser is concerned, the position is now == destination. In reality the
    // motion control system might still be processing the action and the real tool position
    // in any intermediate location.
    set_current_to_destination();
  }

#endif // BEZIER_CURVE_SUPPORT

#if HAS_CONTROLLERFAN

  void controllerFan() {
    static millis_t lastMotorOn = 0; // Last time a motor was turned on
    static millis_t nextMotorCheck = 0; // Last time the state was checked
    millis_t ms = millis();
    if (ELAPSED(ms, nextMotorCheck)) {
      nextMotorCheck = ms + 2500UL; // Not a time critical function, so only check every 2.5s
      if (X_ENABLE_READ == X_ENABLE_ON || Y_ENABLE_READ == Y_ENABLE_ON || Z_ENABLE_READ == Z_ENABLE_ON || thermalManager.soft_pwm_bed > 0
          || E0_ENABLE_READ == E_ENABLE_ON // If any of the drivers are enabled...
          #if E_STEPPERS > 1
            || E1_ENABLE_READ == E_ENABLE_ON
            #if HAS_X2_ENABLE
              || X2_ENABLE_READ == X_ENABLE_ON
            #endif
            #if E_STEPPERS > 2
              || E2_ENABLE_READ == E_ENABLE_ON
              #if E_STEPPERS > 3
                || E3_ENABLE_READ == E_ENABLE_ON
              #endif
            #endif
          #endif
      ) {
        lastMotorOn = ms; //... set time to NOW so the fan will turn on
      }

      // Fan off if no steppers have been enabled for CONTROLLERFAN_SECS seconds
      uint8_t speed = (!lastMotorOn || ELAPSED(ms, lastMotorOn + (CONTROLLERFAN_SECS) * 1000UL)) ? 0 : CONTROLLERFAN_SPEED;

      // allows digital or PWM fan output to be used (see M42 handling)
      digitalWrite(CONTROLLERFAN_PIN, speed);
      analogWrite(CONTROLLERFAN_PIN, speed);
    }
  }

#endif // HAS_CONTROLLERFAN

#if ENABLED(MORGAN_SCARA)

  /**
   * Morgan SCARA Forward Kinematics. Results in cartes[].
   * Maths and first version by QHARLEY.
   * Integrated into Marlin and slightly restructured by Joachim Cerny.
   */
  void forward_kinematics_SCARA(const float &a, const float &b) {

    float a_sin = sin(RADIANS(a)) * L1,
          a_cos = cos(RADIANS(a)) * L1,
          b_sin = sin(RADIANS(b)) * L2,
          b_cos = cos(RADIANS(b)) * L2;

    cartes[X_AXIS] = a_cos + b_cos + SCARA_OFFSET_X;  //theta
    cartes[Y_AXIS] = a_sin + b_sin + SCARA_OFFSET_Y;  //theta+phi

    /*
      SERIAL_ECHOPAIR("SCARA FK Angle a=", a);
      SERIAL_ECHOPAIR(" b=", b);
      SERIAL_ECHOPAIR(" a_sin=", a_sin);
      SERIAL_ECHOPAIR(" a_cos=", a_cos);
      SERIAL_ECHOPAIR(" b_sin=", b_sin);
      SERIAL_ECHOLNPAIR(" b_cos=", b_cos);
      SERIAL_ECHOPAIR(" cartes[X_AXIS]=", cartes[X_AXIS]);
      SERIAL_ECHOLNPAIR(" cartes[Y_AXIS]=", cartes[Y_AXIS]);
    //*/
  }

  /**
   * Morgan SCARA Inverse Kinematics. Results in delta[].
   *
   * See http://forums.reprap.org/read.php?185,283327
   * 
   * Maths and first version by QHARLEY.
   * Integrated into Marlin and slightly restructured by Joachim Cerny.
   */
  void inverse_kinematics(const float logical[XYZ]) {

    static float C2, S2, SK1, SK2, THETA, PSI;

    float sx = RAW_X_POSITION(logical[X_AXIS]) - SCARA_OFFSET_X,  // Translate SCARA to standard X Y
          sy = RAW_Y_POSITION(logical[Y_AXIS]) - SCARA_OFFSET_Y;  // With scaling factor.

    if (L1 == L2)
      C2 = HYPOT2(sx, sy) / L1_2_2 - 1;
    else
      C2 = (HYPOT2(sx, sy) - (L1_2 + L2_2)) / (2.0 * L1 * L2);

    S2 = sqrt(sq(C2) - 1);

    // Unrotated Arm1 plus rotated Arm2 gives the distance from Center to End
    SK1 = L1 + L2 * C2;

    // Rotated Arm2 gives the distance from Arm1 to Arm2
    SK2 = L2 * S2;

    // Angle of Arm1 is the difference between Center-to-End angle and the Center-to-Elbow
    THETA = atan2(SK1, SK2) - atan2(sx, sy);

    // Angle of Arm2
    PSI = atan2(S2, C2);

    delta[A_AXIS] = DEGREES(THETA);        // theta is support arm angle
    delta[B_AXIS] = DEGREES(THETA + PSI);  // equal to sub arm angle (inverted motor)
    delta[C_AXIS] = logical[Z_AXIS];

    /*
      DEBUG_POS("SCARA IK", logical);
      DEBUG_POS("SCARA IK", delta);
      SERIAL_ECHOPAIR("  SCARA (x,y) ", sx);
      SERIAL_ECHOPAIR(",", sy);
      SERIAL_ECHOPAIR(" C2=", C2);
      SERIAL_ECHOPAIR(" S2=", S2);
      SERIAL_ECHOPAIR(" Theta=", THETA);
      SERIAL_ECHOLNPAIR(" Phi=", PHI);
    //*/
  }

#endif // MORGAN_SCARA

#if ENABLED(TEMP_STAT_LEDS)

  static bool red_led = false;
  static millis_t next_status_led_update_ms = 0;

  void handle_status_leds(void) {
    if (ELAPSED(millis(), next_status_led_update_ms)) {
      next_status_led_update_ms += 500; // Update every 0.5s
      float max_temp = 0.0;
      #if HAS_TEMP_BED
        max_temp = MAX3(max_temp, thermalManager.degTargetBed(), thermalManager.degBed());
      #endif
      HOTEND_LOOP() {
        max_temp = MAX3(max_temp, thermalManager.degHotend(e), thermalManager.degTargetHotend(e));
      }
      bool new_led = (max_temp > 55.0) ? true : (max_temp < 54.0) ? false : red_led;
      if (new_led != red_led) {
        red_led = new_led;
        WRITE(STAT_LED_RED_PIN, new_led ? HIGH : LOW);
        WRITE(STAT_LED_BLUE_PIN, new_led ? LOW : HIGH);
      }
    }
  }

#endif

#if ENABLED(FILAMENT_RUNOUT_SENSOR)

  void handle_filament_runout() {
    if (!filament_ran_out) {
      filament_ran_out = true;
      enqueue_and_echo_commands_P(PSTR(FILAMENT_RUNOUT_SCRIPT));
      stepper.synchronize();
    }
  }

#endif // FILAMENT_RUNOUT_SENSOR

#if ENABLED(FAST_PWM_FAN)

  void setPwmFrequency(uint8_t pin, int val) {
    val &= 0x07;
    switch (digitalPinToTimer(pin)) {
      #if defined(TCCR0A)
        case TIMER0A:
        case TIMER0B:
          // TCCR0B &= ~(_BV(CS00) | _BV(CS01) | _BV(CS02));
          // TCCR0B |= val;
          break;
      #endif
      #if defined(TCCR1A)
        case TIMER1A:
        case TIMER1B:
          // TCCR1B &= ~(_BV(CS10) | _BV(CS11) | _BV(CS12));
          // TCCR1B |= val;
          break;
      #endif
      #if defined(TCCR2)
        case TIMER2:
        case TIMER2:
          TCCR2 &= ~(_BV(CS10) | _BV(CS11) | _BV(CS12));
          TCCR2 |= val;
          break;
      #endif
      #if defined(TCCR2A)
        case TIMER2A:
        case TIMER2B:
          TCCR2B &= ~(_BV(CS20) | _BV(CS21) | _BV(CS22));
          TCCR2B |= val;
          break;
      #endif
      #if defined(TCCR3A)
        case TIMER3A:
        case TIMER3B:
        case TIMER3C:
          TCCR3B &= ~(_BV(CS30) | _BV(CS31) | _BV(CS32));
          TCCR3B |= val;
          break;
      #endif
      #if defined(TCCR4A)
        case TIMER4A:
        case TIMER4B:
        case TIMER4C:
          TCCR4B &= ~(_BV(CS40) | _BV(CS41) | _BV(CS42));
          TCCR4B |= val;
          break;
      #endif
      #if defined(TCCR5A)
        case TIMER5A:
        case TIMER5B:
        case TIMER5C:
          TCCR5B &= ~(_BV(CS50) | _BV(CS51) | _BV(CS52));
          TCCR5B |= val;
          break;
      #endif
    }
  }

#endif // FAST_PWM_FAN

float calculate_volumetric_multiplier(float diameter) {
  if (!volumetric_enabled || diameter == 0) return 1.0;
  float d2 = diameter * 0.5;
  return 1.0 / (M_PI * d2 * d2);
}

void calculate_volumetric_multipliers() {
  for (uint8_t i = 0; i < COUNT(filament_size); i++)
    volumetric_multiplier[i] = calculate_volumetric_multiplier(filament_size[i]);
}

void enable_all_steppers() {
  enable_x();
  enable_y();
  enable_z();
  enable_e0();
  enable_e1();
  enable_e2();
  enable_e3();
}

void disable_all_steppers() {
  disable_x();
  disable_y();
  disable_z();
  disable_e0();
  disable_e1();
  disable_e2();
  disable_e3();
}

/**
 * Manage several activities:
 *  - Check for Filament Runout
 *  - Keep the command buffer full
 *  - Check for maximum inactive time between commands
 *  - Check for maximum inactive time between stepper commands
 *  - Check if pin CHDK needs to go LOW
 *  - Check for KILL button held down
 *  - Check for HOME button held down
 *  - Check if cooling fan needs to be switched on
 *  - Check if an idle but hot extruder needs filament extruded (EXTRUDER_RUNOUT_PREVENT)
 */
void manage_inactivity(bool ignore_stepper_queue/*=false*/) {

  #if ENABLED(FILAMENT_RUNOUT_SENSOR)
    if ((IS_SD_PRINTING || print_job_timer.isRunning()) && !(READ(FIL_RUNOUT_PIN) ^ FIL_RUNOUT_INVERTING))
      handle_filament_runout();
  #endif

  if (commands_in_queue < BUFSIZE) get_available_commands();

  millis_t ms = millis();

  if (max_inactive_time && ELAPSED(ms, previous_cmd_ms + max_inactive_time)) kill(PSTR(MSG_KILLED));

  if (stepper_inactive_time && ELAPSED(ms, previous_cmd_ms + stepper_inactive_time)
      && !ignore_stepper_queue && !planner.blocks_queued()) {
    #if ENABLED(DISABLE_INACTIVE_X)
      disable_x();
    #endif
    #if ENABLED(DISABLE_INACTIVE_Y)
      disable_y();
    #endif
    #if ENABLED(DISABLE_INACTIVE_Z)
      disable_z();
    #endif
    #if ENABLED(DISABLE_INACTIVE_E)
      disable_e0();
      disable_e1();
      disable_e2();
      disable_e3();
    #endif
  }

  #ifdef CHDK // Check if pin should be set to LOW after M240 set it to HIGH
    if (chdkActive && PENDING(ms, chdkHigh + CHDK_DELAY)) {
      chdkActive = false;
      WRITE(CHDK, LOW);
    }
  #endif

  #if HAS_KILL

    // Check if the kill button was pressed and wait just in case it was an accidental
    // key kill key press
    // -------------------------------------------------------------------------------
    static int killCount = 0;   // make the inactivity button a bit less responsive
    const int KILL_DELAY = 750;
    if (!READ(KILL_PIN))
      killCount++;
    else if (killCount > 0)
      killCount--;

    // Exceeded threshold and we can confirm that it was not accidental
    // KILL the machine
    // ----------------------------------------------------------------
    if (killCount >= KILL_DELAY) kill(PSTR(MSG_KILLED));
  #endif

  #if HAS_HOME
    // Check to see if we have to home, use poor man's debouncer
    // ---------------------------------------------------------
    static int homeDebounceCount = 0;   // poor man's debouncing count
    const int HOME_DEBOUNCE_DELAY = 2500;
    if (!READ(HOME_PIN)) {
      if (!homeDebounceCount) {
        enqueue_and_echo_commands_P(PSTR("G28"));
        LCD_MESSAGEPGM(MSG_AUTO_HOME);
      }
      if (homeDebounceCount < HOME_DEBOUNCE_DELAY)
        homeDebounceCount++;
      else
        homeDebounceCount = 0;
    }
  #endif

  #if HAS_CONTROLLERFAN
    controllerFan(); // Check if fan should be turned on to cool stepper drivers down
  #endif

  #if ENABLED(EXTRUDER_RUNOUT_PREVENT)
    if (ELAPSED(ms, previous_cmd_ms + (EXTRUDER_RUNOUT_SECONDS) * 1000UL)
      && thermalManager.degHotend(active_extruder) > EXTRUDER_RUNOUT_MINTEMP) {
      bool oldstatus;
      #if ENABLED(SWITCHING_EXTRUDER)
        oldstatus = E0_ENABLE_READ;
        enable_e0();
      #else // !SWITCHING_EXTRUDER
        switch (active_extruder) {
          case 0:
            oldstatus = E0_ENABLE_READ;
            enable_e0();
            break;
          #if E_STEPPERS > 1
            case 1:
              oldstatus = E1_ENABLE_READ;
              enable_e1();
              break;
            #if E_STEPPERS > 2
              case 2:
                oldstatus = E2_ENABLE_READ;
                enable_e2();
                break;
              #if E_STEPPERS > 3
                case 3:
                  oldstatus = E3_ENABLE_READ;
                  enable_e3();
                  break;
              #endif
            #endif
          #endif
        }
      #endif // !SWITCHING_EXTRUDER

      previous_cmd_ms = ms; // refresh_cmd_timeout()
      planner.buffer_line(
        current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS],
        current_position[E_AXIS] + EXTRUDER_RUNOUT_EXTRUDE,
        MMM_TO_MMS(EXTRUDER_RUNOUT_SPEED), active_extruder
      );
      stepper.synchronize();
      planner.set_e_position_mm(current_position[E_AXIS]);
      #if ENABLED(SWITCHING_EXTRUDER)
        E0_ENABLE_WRITE(oldstatus);
      #else
        switch (active_extruder) {
          case 0:
            E0_ENABLE_WRITE(oldstatus);
            break;
          #if E_STEPPERS > 1
            case 1:
              E1_ENABLE_WRITE(oldstatus);
              break;
            #if E_STEPPERS > 2
              case 2:
                E2_ENABLE_WRITE(oldstatus);
                break;
              #if E_STEPPERS > 3
                case 3:
                  E3_ENABLE_WRITE(oldstatus);
                  break;
              #endif
            #endif
          #endif
        }
      #endif // !SWITCHING_EXTRUDER
    }
  #endif // EXTRUDER_RUNOUT_PREVENT

  #if ENABLED(DUAL_X_CARRIAGE)
    // handle delayed move timeout
    if (delayed_move_time && ELAPSED(ms, delayed_move_time + 1000UL) && IsRunning()) {
      // travel moves have been received so enact them
      delayed_move_time = 0xFFFFFFFFUL; // force moves to be done
      set_destination_to_current();
      prepare_move_to_destination();
    }
  #endif

  #if ENABLED(TEMP_STAT_LEDS)
    handle_status_leds();
  #endif

  planner.check_axes_activity();
}

/**
 * Standard idle routine keeps the machine alive
 */
void idle(
  #if ENABLED(FILAMENT_CHANGE_FEATURE)
    bool no_stepper_sleep/*=false*/
  #endif
) {
  lcd_update();
  host_keepalive();
  manage_inactivity(
    #if ENABLED(FILAMENT_CHANGE_FEATURE)
      no_stepper_sleep
    #endif
  );

  thermalManager.manage_heater();

  #if ENABLED(PRINTCOUNTER)
    print_job_timer.tick();
  #endif

  #if HAS_BUZZER && PIN_EXISTS(BEEPER)
    buzzer.tick();
  #endif
}

/**
 * Kill all activity and lock the machine.
 * After this the machine will need to be reset.
 */
void kill(const char* lcd_msg) {
  SERIAL_ERROR_START;
  SERIAL_ERRORLNPGM(MSG_ERR_KILLED);

  #if ENABLED(ULTRA_LCD)
    kill_screen(lcd_msg);
  #else
    UNUSED(lcd_msg);
  #endif

  delay(500); // Wait a short time

  cli(); // Stop interrupts
  thermalManager.disable_all_heaters();
  disable_all_steppers();

  #if HAS_POWER_SWITCH
    pinMode(PS_ON_PIN, INPUT);
  #endif

  suicide();
  while (1) {
    #if ENABLED(USE_WATCHDOG)
      watchdog_reset();
    #endif
  } // Wait for reset
}

/**
 * Turn off heaters and stop the print in progress
 * After a stop the machine may be resumed with M999
 */
void stop() {
  thermalManager.disable_all_heaters();
  if (IsRunning()) {
    Running = false;
    Stopped_gcode_LastN = gcode_LastN; // Save last g_code for restart
    SERIAL_ERROR_START;
    SERIAL_ERRORLNPGM(MSG_ERR_STOPPED);
    LCD_MESSAGEPGM(MSG_STOPPED);
  }
}

/**
 * Marlin entry-point: Set up before the program loop
 *  - Set up the kill pin, filament runout, power hold
 *  - Start the serial port
 *  - Print startup messages and diagnostics
 *  - Get EEPROM or default settings
 *  - Initialize managers for:
 *    • temperature
 *    • planner
 *    • watchdog
 *    • stepper
 *    • photo pin
 *    • servos
 *    • LCD controller
 *    • Digipot I2C
 *    • Z probe sled
 *    • status LEDs
 */
void setup() {

  #ifdef DISABLE_JTAG
    // Disable JTAG on AT90USB chips to free up pins for IO
    MCUCR = 0x80;
    MCUCR = 0x80;
  #endif

  #if ENABLED(FILAMENT_RUNOUT_SENSOR)
    setup_filrunoutpin();
  #endif

  setup_killpin();

  setup_powerhold();

  #if HAS_STEPPER_RESET
    disableStepperDrivers();
  #endif

  MYSERIAL.begin(BAUDRATE);
  SERIAL_PROTOCOLLNPGM("start");
  SERIAL_ECHO_START;

  // Check startup - does nothing if bootloader sets MCUSR to 0
  byte mcu = MCUSR;
  if (mcu & 1) SERIAL_ECHOLNPGM(MSG_POWERUP);
  if (mcu & 2) SERIAL_ECHOLNPGM(MSG_EXTERNAL_RESET);
  if (mcu & 4) SERIAL_ECHOLNPGM(MSG_BROWNOUT_RESET);
  if (mcu & 8) SERIAL_ECHOLNPGM(MSG_WATCHDOG_RESET);
  if (mcu & 32) SERIAL_ECHOLNPGM(MSG_SOFTWARE_RESET);
  MCUSR = 0;

  SERIAL_ECHOPGM(MSG_MARLIN);
  SERIAL_CHAR(' ');
  SERIAL_ECHOLNPGM(SHORT_BUILD_VERSION);
  SERIAL_EOL;

  #if defined(STRING_DISTRIBUTION_DATE) && defined(STRING_CONFIG_H_AUTHOR)
    SERIAL_ECHO_START;
    SERIAL_ECHOPGM(MSG_CONFIGURATION_VER);
    SERIAL_ECHOPGM(STRING_DISTRIBUTION_DATE);
    SERIAL_ECHOLNPGM(MSG_AUTHOR STRING_CONFIG_H_AUTHOR);
    SERIAL_ECHOLNPGM("Compiled: " __DATE__);
  #endif

  SERIAL_ECHO_START;
  SERIAL_ECHOPAIR(MSG_FREE_MEMORY, freeMemory());
  SERIAL_ECHOLNPAIR(MSG_PLANNER_BUFFER_BYTES, (int)sizeof(block_t)*BLOCK_BUFFER_SIZE);

  // Send "ok" after commands by default
  for (int8_t i = 0; i < BUFSIZE; i++) send_ok[i] = true;

  // Load data from EEPROM if available (or use defaults)
  // This also updates variables in the planner, elsewhere
  Config_RetrieveSettings();

  // Initialize current position based on home_offset
  memcpy(current_position, home_offset, sizeof(home_offset));

  // Vital to init stepper/planner equivalent for current_position
  SYNC_PLAN_POSITION_KINEMATIC();

  thermalManager.init();    // Initialize temperature loop

  #if ENABLED(USE_WATCHDOG)
    watchdog_init();
  #endif

  stepper.init();    // Initialize stepper, this enables interrupts!
  setup_photpin();
  servo_init();

  #if HAS_BED_PROBE
    endstops.enable_z_probe(false);
  #endif

  #if HAS_CONTROLLERFAN
    SET_OUTPUT(CONTROLLERFAN_PIN); //Set pin used for driver cooling fan
  #endif

  #if HAS_STEPPER_RESET
    enableStepperDrivers();
  #endif

  #if ENABLED(DIGIPOT_I2C)
    digipot_i2c_init();
  #endif

  #if ENABLED(DAC_STEPPER_CURRENT)
    dac_init();
  #endif

  #if ENABLED(Z_PROBE_SLED) && PIN_EXISTS(SLED)
    OUT_WRITE(SLED_PIN, LOW); // turn it off
  #endif // Z_PROBE_SLED

  setup_homepin();

  #if PIN_EXISTS(STAT_LED_RED)
    OUT_WRITE(STAT_LED_RED_PIN, LOW); // turn it off
  #endif

  #if PIN_EXISTS(STAT_LED_BLUE)
    OUT_WRITE(STAT_LED_BLUE_PIN, LOW); // turn it off
  #endif

  lcd_init();
  #if ENABLED(SHOW_BOOTSCREEN)
    #if ENABLED(DOGLCD)
      safe_delay(BOOTSCREEN_TIMEOUT);
    #elif ENABLED(ULTRA_LCD)
      bootscreen();
      lcd_init();
    #endif
  #endif

  #if ENABLED(MIXING_EXTRUDER) && MIXING_VIRTUAL_TOOLS > 1
    // Initialize mixing to 100% color 1
    for (uint8_t i = 0; i < MIXING_STEPPERS; i++)
      mixing_factor[i] = (i == 0) ? 1 : 0;
    for (uint8_t t = 0; t < MIXING_VIRTUAL_TOOLS; t++)
      for (uint8_t i = 0; i < MIXING_STEPPERS; i++)
        mixing_virtual_tool_mix[t][i] = mixing_factor[i];
  #endif

  #if ENABLED(EXPERIMENTAL_I2CBUS) && I2C_SLAVE_ADDRESS > 0
    i2c.onReceive(i2c_on_receive);
    i2c.onRequest(i2c_on_request);
  #endif
}

/**
 * The main Marlin program loop
 *
 *  - Save or log commands to SD
 *  - Process available commands (if not saving)
 *  - Call heater manager
 *  - Call inactivity manager
 *  - Call endstop manager
 *  - Call LCD update
 */
void loop() {
  if (commands_in_queue < BUFSIZE) get_available_commands();

  #if ENABLED(SDSUPPORT)
    card.checkautostart(false);
  #endif

  if (commands_in_queue) {

    #if ENABLED(SDSUPPORT)

      if (card.saving) {
        char* command = command_queue[cmd_queue_index_r];
        if (strstr_P(command, PSTR("M29"))) {
          // M29 closes the file
          card.closefile();
          SERIAL_PROTOCOLLNPGM(MSG_FILE_SAVED);
          ok_to_send();
        }
        else {
          // Write the string from the read buffer to SD
          card.write_command(command);
          if (card.logging)
            process_next_command(); // The card is saving because it's logging
          else
            ok_to_send();
        }
      }
      else
        process_next_command();

    #else

      process_next_command();

    #endif // SDSUPPORT

    // The queue may be reset by a command handler or by code invoked by idle() within a handler
    if (commands_in_queue) {
      --commands_in_queue;
      cmd_queue_index_r = (cmd_queue_index_r + 1) % BUFSIZE;
    }
  }
  endstops.report_state();
  idle();
}