♻️ Adjust LCD init, contrast default, settings load

Marlin/src/HAL/LPC1768/inc/SanityCheck.h

   #define _IS_RX1_1 IS_RX1
   #if IS_TX1(TMC_SW_SCK)
     #error "Serial port pins (1) conflict with other pins!"
-  #elif HAS_WIRED_LCD
+  #elif HAS_ROTARY_ENCODER
     #if IS_TX1(BTN_EN2) || IS_RX1(BTN_EN1)
       #error "Serial port pins (1) conflict with Encoder Buttons!"
     #elif ANY_TX(1, SD_SCK_PIN, LCD_PINS_D4, DOGLCD_SCK, LCD_RESET_PIN, LCD_PINS_RS, SHIFT_CLK_PIN) \

Marlin/src/MarlinCore.cpp

   // UI must be initialized before EEPROM
   // (because EEPROM code calls the UI).
 
-  #if HAS_DWIN_E3V2_BASIC
-    SETUP_RUN(DWIN_Startup());
-  #else
-    SETUP_RUN(ui.init());
-    #if BOTH(HAS_WIRED_LCD, SHOW_BOOTSCREEN)
-      SETUP_RUN(ui.show_bootscreen());
-      const millis_t bootscreen_ms = millis();
-    #endif
-    SETUP_RUN(ui.reset_status());     // Load welcome message early. (Retained if no errors exist.)
-  #endif
+  SETUP_RUN(ui.init());
 
   #if PIN_EXISTS(SAFE_POWER)
     #if HAS_DRIVER_SAFE_POWER_PROTECT
     #endif
   #endif
 
-  #if ENABLED(PROBE_TARE)
-    SETUP_RUN(probe.tare_init());
-  #endif
-
   #if BOTH(SDSUPPORT, SDCARD_EEPROM_EMULATION)
     SETUP_RUN(card.mount());          // Mount media with settings before first_load
   #endif
   SETUP_RUN(settings.first_load());   // Load data from EEPROM if available (or use defaults)
                                       // This also updates variables in the planner, elsewhere
 
+  #if BOTH(HAS_WIRED_LCD, SHOW_BOOTSCREEN)
+    SETUP_RUN(ui.show_bootscreen());
+    const millis_t bootscreen_ms = millis();
+  #endif
+
+  #if ENABLED(PROBE_TARE)
+    SETUP_RUN(probe.tare_init());
+  #endif
+
   #if HAS_ETHERNET
     SETUP_RUN(ethernet.init());
   #endif

Marlin/src/gcode/lcd/M250.cpp

  * M250: Read and optionally set the LCD contrast
  */
 void GcodeSuite::M250() {
-  if (parser.seenval('C'))
+  if (LCD_CONTRAST_MIN < LCD_CONTRAST_MAX && parser.seenval('C'))
     ui.set_contrast(parser.value_byte());
   else
     M250_report();

Marlin/src/inc/Conditionals_LCD.h

   #define LCD_HEIGHT                  10    // Character lines
   #define LCD_CONTRAST_MIN            127
   #define LCD_CONTRAST_MAX            255
-  #define DEFAULT_LCD_CONTRAST        250
+  #define LCD_CONTRAST_DEFAULT        250
   #define CONVERT_TO_EXT_ASCII        // Use extended 128-255 symbols from ASCII table.
                                       // At this time present conversion only for cyrillic - bg, ru and uk languages.
                                       // First 7 ASCII symbols in panel font must be replaced with Marlin's special symbols.

Marlin/src/inc/Conditionals_post.h

 #elif EITHER(MKS_MINI_12864_V3, BTT_MINI_12864_V1)
   #define _LCD_CONTRAST_MIN  255
   #define _LCD_CONTRAST_INIT 255
-  #define _LCD_CONTRAST_MAX  255
 #elif ENABLED(FYSETC_MINI_12864)
   #define _LCD_CONTRAST_INIT 220
 #elif ENABLED(ULTI_CONTROLLER)
 #elif ENABLED(ZONESTAR_12864OLED)
   #define _LCD_CONTRAST_MIN   64
   #define _LCD_CONTRAST_INIT 128
-  #define _LCD_CONTRAST_MAX  255
 #elif IS_TFTGLCD_PANEL
-  #define _LCD_CONTRAST_MIN    0
   #define _LCD_CONTRAST_INIT 250
-  #define _LCD_CONTRAST_MAX  255
 #endif
 
 #ifdef _LCD_CONTRAST_INIT
   #define HAS_LCD_CONTRAST 1
-#endif
-
-#if HAS_LCD_CONTRAST
   #ifndef LCD_CONTRAST_MIN
     #ifdef _LCD_CONTRAST_MIN
       #define LCD_CONTRAST_MIN _LCD_CONTRAST_MIN
       #define LCD_CONTRAST_MAX 63   // ST7567 6-bits contrast
     #endif
   #endif
-  #ifndef DEFAULT_LCD_CONTRAST
-    #define DEFAULT_LCD_CONTRAST LCD_CONTRAST_INIT
+  #ifndef LCD_CONTRAST_DEFAULT
+    #define LCD_CONTRAST_DEFAULT LCD_CONTRAST_INIT
   #endif
 #endif
 

Marlin/src/inc/Warnings.cpp

 #if CANNOT_EMBED_CONFIGURATION
   #warning "Disabled CONFIGURATION_EMBEDDING because the target usually has less flash storage. Define FORCE_CONFIG_EMBED to override."
 #endif
+
+#if HAS_LCD_CONTRAST && LCD_CONTRAST_MIN >= LCD_CONTRAST_MAX
+  #warning "Contrast cannot be changed when LCD_CONTRAST_MIN >= LCD_CONTRAST_MAX."
+#endif

Marlin/src/lcd/e3v2/creality/dwin.cpp

 
 void HMI_SDCardInit() { card.cdroot(); }
 
+// Initialize or re-initialize the LCD
+void MarlinUI::init_lcd() { DWIN_Startup(); }
+
 void MarlinUI::refresh() { /* Nothing to see here */ }
 
 #if HAS_LCD_BRIGHTNESS

Marlin/src/lcd/e3v2/enhanced/dwin.cpp

 
 void HMI_SDCardInit() { card.cdroot(); }
 
+// Initialize or re-initialize the LCD
+void MarlinUI::init_lcd() { DWIN_Startup(); }
+
 void MarlinUI::refresh() { /* Nothing to see here */ }
 
 #if HAS_LCD_BRIGHTNESS

Marlin/src/lcd/e3v2/jyersui/dwin.cpp

   Redraw_Screen();
 }
 
-void MarlinUI::init() {
+void MarlinUI::init_lcd() {
   delay(800);
   SERIAL_ECHOPGM("\nDWIN handshake ");
   if (DWIN_Handshake()) SERIAL_ECHOLNPGM("ok."); else SERIAL_ECHOLNPGM("error.");

Marlin/src/lcd/e3v2/marlinui/ui_common.cpp

 bool MarlinUI::detected() { return true; }
 
 // Initialize or re-initialize the LCD
-void MarlinUI::init_lcd() {
-  DWIN_Startup();
-}
+void MarlinUI::init_lcd() { DWIN_Startup(); }
 
 // This LCD should clear where it will draw anew
 void MarlinUI::clear_lcd() {

Marlin/src/lcd/extui/ui_api.cpp

 
 // At the moment we hook into MarlinUI methods, but this could be cleaned up in the future
 
-void MarlinUI::init() { ExtUI::onStartup(); }
+void MarlinUI::init_lcd() { ExtUI::onStartup(); }
 
 void MarlinUI::update() { ExtUI::onIdle(); }
 

Marlin/src/lcd/marlinui.cpp

 #if HAS_DISPLAY
   #include "../gcode/queue.h"
   #include "fontutils.h"
-  #include "../sd/cardreader.h"
 #endif
 
 #if ENABLED(DWIN_CREALITY_LCD)
 
 #endif
 
+// Encoder Handling
+#if HAS_ENCODER_ACTION
+  uint32_t MarlinUI::encoderPosition;
+  volatile int8_t encoderDiff; // Updated in update_buttons, added to encoderPosition every LCD update
+#endif
+
+void MarlinUI::init() {
+
+  init_lcd();
+
+  #if HAS_DIGITAL_BUTTONS
+    #if BUTTON_EXISTS(EN1)
+      SET_INPUT_PULLUP(BTN_EN1);
+    #endif
+    #if BUTTON_EXISTS(EN2)
+      SET_INPUT_PULLUP(BTN_EN2);
+    #endif
+    #if BUTTON_EXISTS(ENC)
+      SET_INPUT_PULLUP(BTN_ENC);
+    #endif
+    #if BUTTON_EXISTS(ENC_EN)
+      SET_INPUT_PULLUP(BTN_ENC_EN);
+    #endif
+    #if BUTTON_EXISTS(BACK)
+      SET_INPUT_PULLUP(BTN_BACK);
+    #endif
+    #if BUTTON_EXISTS(UP)
+      SET_INPUT(BTN_UP);
+    #endif
+    #if BUTTON_EXISTS(DWN)
+      SET_INPUT(BTN_DWN);
+    #endif
+    #if BUTTON_EXISTS(LFT)
+      SET_INPUT(BTN_LFT);
+    #endif
+    #if BUTTON_EXISTS(RT)
+      SET_INPUT(BTN_RT);
+    #endif
+  #endif
+
+  #if HAS_SHIFT_ENCODER
+
+    #if ENABLED(SR_LCD_2W_NL) // Non latching 2 wire shift register
+
+      SET_OUTPUT(SR_DATA_PIN);
+      SET_OUTPUT(SR_CLK_PIN);
+
+    #elif PIN_EXISTS(SHIFT_CLK)
+
+      SET_OUTPUT(SHIFT_CLK_PIN);
+      OUT_WRITE(SHIFT_LD_PIN, HIGH);
+      #if PIN_EXISTS(SHIFT_EN)
+        OUT_WRITE(SHIFT_EN_PIN, LOW);
+      #endif
+      SET_INPUT_PULLUP(SHIFT_OUT_PIN);
+
+    #endif
+
+  #endif // HAS_SHIFT_ENCODER
+
+  #if BOTH(HAS_ENCODER_ACTION, HAS_SLOW_BUTTONS)
+    slow_buttons = 0;
+  #endif
+
+  update_buttons();
+
+  TERN_(HAS_ENCODER_ACTION, encoderDiff = 0);
+
+  reset_status(); // Set welcome message
+}
+
 #if HAS_WIRED_LCD
 
   #if HAS_MARLINUI_U8GLIB
 
   #include "lcdprint.h"
 
-  #include "../sd/cardreader.h"
-
   #include "../module/temperature.h"
   #include "../module/planner.h"
   #include "../module/motion.h"
     bool MarlinUI::old_is_printing;
   #endif
 
-  // Encoder Handling
-  #if HAS_ENCODER_ACTION
-    uint32_t MarlinUI::encoderPosition;
-    volatile int8_t encoderDiff; // Updated in update_buttons, added to encoderPosition every LCD update
-  #endif
-
   #if ENABLED(SDSUPPORT)
 
-    #include "../sd/cardreader.h"
-
     #if MARLINUI_SCROLL_NAME
       uint8_t MarlinUI::filename_scroll_pos, MarlinUI::filename_scroll_max;
     #endif
 
   #endif // HAS_LCD_MENU
 
-  void MarlinUI::init() {
-
-    init_lcd();
-
-    #if HAS_DIGITAL_BUTTONS
-      #if BUTTON_EXISTS(EN1)
-        SET_INPUT_PULLUP(BTN_EN1);
-      #endif
-      #if BUTTON_EXISTS(EN2)
-        SET_INPUT_PULLUP(BTN_EN2);
-      #endif
-      #if BUTTON_EXISTS(ENC)
-        SET_INPUT_PULLUP(BTN_ENC);
-      #endif
-      #if BUTTON_EXISTS(ENC_EN)
-        SET_INPUT_PULLUP(BTN_ENC_EN);
-      #endif
-      #if BUTTON_EXISTS(BACK)
-        SET_INPUT_PULLUP(BTN_BACK);
-      #endif
-      #if BUTTON_EXISTS(UP)
-        SET_INPUT(BTN_UP);
-      #endif
-      #if BUTTON_EXISTS(DWN)
-        SET_INPUT(BTN_DWN);
-      #endif
-      #if BUTTON_EXISTS(LFT)
-        SET_INPUT(BTN_LFT);
-      #endif
-      #if BUTTON_EXISTS(RT)
-        SET_INPUT(BTN_RT);
-      #endif
-    #endif
-
-    #if HAS_SHIFT_ENCODER
-
-      #if ENABLED(SR_LCD_2W_NL) // Non latching 2 wire shift register
-
-        SET_OUTPUT(SR_DATA_PIN);
-        SET_OUTPUT(SR_CLK_PIN);
-
-      #elif PIN_EXISTS(SHIFT_CLK)
-
-        SET_OUTPUT(SHIFT_CLK_PIN);
-        OUT_WRITE(SHIFT_LD_PIN, HIGH);
-        #if PIN_EXISTS(SHIFT_EN)
-          OUT_WRITE(SHIFT_EN_PIN, LOW);
-        #endif
-        SET_INPUT_PULLUP(SHIFT_OUT_PIN);
-
-      #endif
-
-    #endif // HAS_SHIFT_ENCODER
-
-    #if BOTH(HAS_ENCODER_ACTION, HAS_SLOW_BUTTONS)
-      slow_buttons = 0;
-    #endif
-
-    update_buttons();
-
-    TERN_(HAS_ENCODER_ACTION, encoderDiff = 0);
-  }
-
   ////////////////////////////////////////////
   ///////////// Keypad Handling //////////////
   ////////////////////////////////////////////
           next_filament_display = millis() + 5000UL;  // Show status message for 5s
         #endif
         goto_screen(menu_main);
-        #if DISABLED(NO_LCD_REINIT)
-          init_lcd(); // May revive the LCD if static electricity killed it
-        #endif
+        IF_DISABLED(NO_LCD_REINIT, init_lcd()); // May revive the LCD if static electricity killed it
         return;
       }
 

Marlin/src/lcd/marlinui.h

  */
 #pragma once
 
+#include "../sd/cardreader.h"
 #include "../module/motion.h"
 #include "buttons.h"
 
   #include "../libs/buzzer.h"
 #endif
 
-#if ENABLED(SDSUPPORT)
-  #include "../sd/cardreader.h"
-#endif
-
 #if ENABLED(TOUCH_SCREEN_CALIBRATION)
   #include "tft_io/touch_calibration.h"
 #endif
     TERN_(HAS_LCD_MENU, currentScreen = status_screen);
   }
 
+  static void init();
+
+  #if HAS_DISPLAY || HAS_DWIN_E3V2
+    static void init_lcd();
+  #else
+    static void init_lcd() {}
+  #endif
+
+  #if HAS_WIRED_LCD
+    static bool detected();
+  #else
+    static bool detected() { return true; }
+  #endif
+
   #if HAS_MULTI_LANGUAGE
     static uint8_t language;
     static void set_language(const uint8_t lang);
     }
   #endif
 
-  #if HAS_WIRED_LCD
-    static bool detected();
-    static void init_lcd();
-  #else
-    static bool detected() { return true; }
-    static void init_lcd() {}
-  #endif
-
   #if HAS_PRINT_PROGRESS
     #if HAS_PRINT_PROGRESS_PERMYRIAD
       typedef uint16_t progress_t;
 
   #if HAS_DISPLAY
 
-    static void init();
     static void update();
 
     static void abort_print();
 
   #else // No LCD
 
-    static void init() {}
     static void update() {}
     static void return_to_status() {}
 

Marlin/src/lcd/menu/menu_configuration.cpp

   #if HAS_LCD_BRIGHTNESS
     EDIT_ITEM_FAST(uint8, MSG_BRIGHTNESS, &ui.brightness, LCD_BRIGHTNESS_MIN, LCD_BRIGHTNESS_MAX, ui.refresh_brightness, true);
   #endif
-  #if HAS_LCD_CONTRAST
+  #if HAS_LCD_CONTRAST && LCD_CONTRAST_MIN < LCD_CONTRAST_MAX
     EDIT_ITEM_FAST(uint8, MSG_CONTRAST, &ui.contrast, LCD_CONTRAST_MIN, LCD_CONTRAST_MAX, ui.refresh_contrast, true);
   #endif
   #if ENABLED(FWRETRACT)

Marlin/src/module/settings.cpp

       //
       #if HAS_USER_THERMISTORS
       {
+        user_thermistor_t user_thermistor[USER_THERMISTORS];
         _FIELD_TEST(user_thermistor);
-        EEPROM_READ(thermalManager.user_thermistor);
+        EEPROM_READ(user_thermistor);
+        if (!validating) COPY(thermalManager.user_thermistor, user_thermistor);
       }
       #endif
 
       // Power monitor
       //
       {
-        #if HAS_POWER_MONITOR
-          uint8_t &power_monitor_flags = power_monitor.flags;
-        #else
-          uint8_t power_monitor_flags;
-        #endif
+        uint8_t power_monitor_flags;
         _FIELD_TEST(power_monitor_flags);
         EEPROM_READ(power_monitor_flags);
+        TERN_(HAS_POWER_MONITOR, if (!validating) power_monitor.flags = power_monitor_flags);
       }
 
       //
       // LCD Brightness
       //
       {
-        _FIELD_TEST(lcd_brightness);
         uint8_t lcd_brightness;
         EEPROM_READ(lcd_brightness);
         TERN_(HAS_LCD_BRIGHTNESS, if (!validating) ui.set_brightness(lcd_brightness));
       // Controller Fan
       //
       {
+        controllerFan_settings_t cfs = { 0 };
         _FIELD_TEST(controllerFan_settings);
-        #if ENABLED(CONTROLLER_FAN_EDITABLE)
-          const controllerFan_settings_t &cfs = controllerFan.settings;
-        #else
-          controllerFan_settings_t cfs = { 0 };
-        #endif
         EEPROM_READ(cfs);
+        TERN_(CONTROLLER_FAN_EDITABLE, if (!validating) controllerFan.settings = cfs);
       }
 
       //
       // Power-Loss Recovery
       //
       {
+        bool recovery_enabled;
         _FIELD_TEST(recovery_enabled);
-        #if ENABLED(POWER_LOSS_RECOVERY)
-          const bool &recovery_enabled = recovery.enabled;
-        #else
-          bool recovery_enabled;
-        #endif
         EEPROM_READ(recovery_enabled);
+        TERN_(POWER_LOSS_RECOVERY, if (!validating) recovery.enabled = recovery_enabled);
       }
 
       //
       // Firmware Retraction
       //
       {
+        fwretract_settings_t fwretract_settings;
+        bool autoretract_enabled;
         _FIELD_TEST(fwretract_settings);
+        EEPROM_READ(fwretract_settings);
+        EEPROM_READ(autoretract_enabled);
 
         #if ENABLED(FWRETRACT)
-          EEPROM_READ(fwretract.settings);
-        #else
-          fwretract_settings_t fwretract_settings;
-          EEPROM_READ(fwretract_settings);
-        #endif
-        #if BOTH(FWRETRACT, FWRETRACT_AUTORETRACT)
-          EEPROM_READ(fwretract.autoretract_enabled);
-        #else
-          bool autoretract_enabled;
-          EEPROM_READ(autoretract_enabled);
+          if (!validating) {
+            fwretract.settings = fwretract_settings;
+            TERN_(FWRETRACT_AUTORETRACT, fwretract.autoretract_enabled = autoretract_enabled);
+          }
         #endif
       }
 

Marlin/src/pins/mega/pins_GT2560_REV_A.h

 
       #define LCD_RESET_PIN                   16
 
-      #define DEFAULT_LCD_CONTRAST           220
+      #define LCD_CONTRAST_DEFAULT           220
 
       #define LCD_BACKLIGHT_PIN               -1
     #else

Marlin/src/pins/mega/pins_HJC2560C_REV2.h

     #if ENABLED(HJC_LCD_SMART_CONTROLLER)
       #define LCD_BACKLIGHT_PIN                5  // LCD_Backlight
       //#ifndef LCD_CONTRAST_PIN
-      //  #define LCD_CONTRAST_PIN  5   // LCD_Contrast
+      //  #define LCD_CONTRAST_PIN             5  // LCD_Contrast
       //#endif
       #ifndef FIL_RUNOUT_PIN
         #define FIL_RUNOUT_PIN                24  // Filament runout

Marlin/src/pins/ramps/pins_K8800.h

 
   #define LCD_CONTRAST_MIN                     0
   #define LCD_CONTRAST_MAX                   100
-  #define DEFAULT_LCD_CONTRAST                30
+  #define LCD_CONTRAST_DEFAULT                30
   //#define LCD_SCREEN_ROTATE                180  // 0, 90, 180, 270
 
   #if IS_NEWPANEL

Marlin/src/pins/stm32f4/pins_ARTILLERY_RUBY.h

       #define NEOPIXEL_PIN                  PB9
     #endif
 
-    #define DEFAULT_LCD_CONTRAST             255
+    #define LCD_CONTRAST_DEFAULT             255
   #else
     #define LCD_PINS_RS                     PC15
     #define LCD_PINS_ENABLE                 PB6