Use native ADC resolution where possible (#15719)

Marlin/src/HAL/HAL.h

@@ -25,6 +25,8 @@
 
 #include HAL_PATH(.,HAL.h)
 
+#define HAL_ADC_RANGE _BV(HAL_ADC_RESOLUTION)
+
 inline void watchdog_refresh() {
   #if ENABLED(USE_WATCHDOG)
     HAL_watchdog_refresh();

Marlin/src/HAL/HAL_AVR/HAL.h

@@ -365,6 +365,7 @@ inline void HAL_adc_init() {
   #define HAL_START_ADC(pin) ADCSRB = 0; SET_ADMUX_ADCSRA(pin)
 #endif
 
+#define HAL_ADC_RESOLUTION 10
 #define HAL_READ_ADC()  ADC
 #define HAL_ADC_READY() !TEST(ADCSRA, ADSC)
 

Marlin/src/HAL/HAL_DUE/HAL.h

@@ -133,6 +133,7 @@ extern uint16_t HAL_adc_result;     // result of last ADC conversion
 inline void HAL_adc_init() {}//todo
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_result
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_ESP32/HAL.h

@@ -111,6 +111,7 @@ void eeprom_update_block (const void *__src, void *__dst, size_t __n);
 void HAL_adc_init();
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_result
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_LINUX/HAL.h

@@ -89,6 +89,7 @@ int freeMemory();
 // ADC
 #define HAL_ANALOG_SELECT(pin) HAL_adc_enable_channel(pin)
 #define HAL_START_ADC(pin)     HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION     10
 #define HAL_READ_ADC()         HAL_adc_get_result()
 #define HAL_ADC_READY()        true
 

Marlin/src/HAL/HAL_LPC1768/HAL.h

@@ -131,11 +131,14 @@ int freeMemory();
                                     // K = 6, 565 samples, 500Hz sample rate, 1.13s convergence on full range step
                                     // Memory usage per ADC channel (bytes): 4 (32 Bytes for 8 channels)
 
-using FilteredADC = LPC176x::ADC<ADC_LOWPASS_K_VALUE, ADC_MEDIAN_FILTER_SIZE>;
+#define HAL_ADC_RESULT_BITS    12   // 15 bit maximum, raw temperature is stored as int16_t
+#define HAL_ADC_FILTERED            // Disable oversampling done in Marlin as ADC values already filtered in HAL
+#define HAL_ADC_RESOLUTION     HAL_ADC_RESULT_BITS
 
+using FilteredADC = LPC176x::ADC<ADC_LOWPASS_K_VALUE, ADC_MEDIAN_FILTER_SIZE>;
 extern uint32_t HAL_adc_reading;
 [[gnu::always_inline]] inline void HAL_start_adc(const pin_t pin) {
-  HAL_adc_reading = FilteredADC::read(pin) >> 6; // returns 16bit value, reduce to 10bit
+  HAL_adc_reading = FilteredADC::read(pin) >> (16 - HAL_ADC_RESULT_BITS); // returns 16bit value, reduce to required bits
 }
 [[gnu::always_inline]] inline uint16_t HAL_read_adc() {
   return HAL_adc_reading;

Marlin/src/HAL/HAL_SAMD51/HAL.h

@@ -110,6 +110,7 @@ extern uint16_t HAL_adc_result;     // result of last ADC conversion
 void HAL_adc_init();
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_result
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_STM32/HAL.h

@@ -188,6 +188,7 @@ void eeprom_update_block(const void *__src, void *__dst, size_t __n);
 inline void HAL_adc_init() {}
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_result
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_STM32F1/HAL.h

@@ -238,6 +238,7 @@ void eeprom_update_block(const void *__src, void *__dst, size_t __n);
 void HAL_adc_init();
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_result
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_STM32_F4_F7/HAL.h

@@ -208,6 +208,7 @@ void eeprom_update_block (const void *__src, void *__dst, size_t __n);
 inline void HAL_adc_init() {}
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_result
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_TEENSY31_32/HAL.h

@@ -109,6 +109,7 @@ extern "C" {
 void HAL_adc_init();
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_get_result()
 #define HAL_ADC_READY()     true
 

Marlin/src/HAL/HAL_TEENSY35_36/HAL.h

@@ -115,6 +115,7 @@ extern "C" {
 void HAL_adc_init();
 
 #define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
+#define HAL_ADC_RESOLUTION  10
 #define HAL_READ_ADC()      HAL_adc_get_result()
 #define HAL_ADC_READY()     true
 

Marlin/src/feature/filwidth.h

@@ -23,6 +23,7 @@
 
 #include "../inc/MarlinConfig.h"
 #include "../module/planner.h"
+#include "../module/thermistor/thermistors.h"
 
 class FilamentWidthSensor {
 public:
@@ -66,7 +67,7 @@ public:
   }
 
   // Convert raw measurement to mm
-  static inline float raw_to_mm(const uint16_t v) { return v * 5.0f * RECIPROCAL(16383.0f); }
+  static inline float raw_to_mm(const uint16_t v) { return v * 5.0f * RECIPROCAL(float(MAX_RAW_THERMISTOR_VALUE)); }
   static inline float raw_to_mm() { return raw_to_mm(raw); }
 
   // A scaled reading is ready

Marlin/src/lcd/ultralcd.cpp

@@ -103,6 +103,10 @@
   #include "../feature/tmc_util.h"
 #endif
 
+#if HAS_ADC_BUTTONS
+  #include "../module/thermistor/thermistors.h"
+#endif
+
 #if HAS_ENCODER_ACTION
   volatile uint8_t MarlinUI::buttons;
   #if HAS_SLOW_BUTTONS
@@ -1102,31 +1106,33 @@ void MarlinUI::update() {
   #endif
 
   // Calculate the ADC value for the voltage divider with specified pull-down resistor value
-  #define ADC_BUTTON_VALUE(r)  (int(4096.0 * (ADC_BUTTONS_VALUE_SCALE) * r / (r + ADC_BUTTONS_R_PULLUP)))
+  #define ADC_BUTTON_VALUE(r)  int(HAL_ADC_RANGE * (ADC_BUTTONS_VALUE_SCALE) * r / (r + ADC_BUTTONS_R_PULLUP))
 
+  static constexpr uint16_t adc_button_tolerance = HAL_ADC_RANGE *   25 / 1024,
+                                adc_other_button = HAL_ADC_RANGE * 1000 / 1024;
   static const _stADCKeypadTable_ stADCKeyTable[] PROGMEM = {
     // VALUE_MIN, VALUE_MAX, KEY
-    { 4000, 4096, 1 + BLEN_KEYPAD_F1     }, // F1
-    { 4000, 4096, 1 + BLEN_KEYPAD_F2     }, // F2
-    { 4000, 4096, 1 + BLEN_KEYPAD_F3     }, // F3
-    {  ADC_BUTTON_VALUE(ADC_BUTTONS_LEFT_R_PULLDOWN)   - 100,
-       ADC_BUTTON_VALUE(ADC_BUTTONS_LEFT_R_PULLDOWN)   + 100, 1 + BLEN_KEYPAD_LEFT   }, // LEFT  ( 272 ...  472)
-    {  ADC_BUTTON_VALUE(ADC_BUTTONS_RIGHT_R_PULLDOWN)  - 100,
-       ADC_BUTTON_VALUE(ADC_BUTTONS_RIGHT_R_PULLDOWN)  + 100, 1 + BLEN_KEYPAD_RIGHT  }, // RIGHT (1948 ... 2148)
-    {  ADC_BUTTON_VALUE(ADC_BUTTONS_UP_R_PULLDOWN)     - 100,
-       ADC_BUTTON_VALUE(ADC_BUTTONS_UP_R_PULLDOWN)     + 100, 1 + BLEN_KEYPAD_UP     }, // UP    ( 618 ...  818)
-    {  ADC_BUTTON_VALUE(ADC_BUTTONS_DOWN_R_PULLDOWN)   - 100,
-       ADC_BUTTON_VALUE(ADC_BUTTONS_DOWN_R_PULLDOWN)   + 100, 1 + BLEN_KEYPAD_DOWN   }, // DOWN  (2686 ... 2886)
-    {  ADC_BUTTON_VALUE(ADC_BUTTONS_MIDDLE_R_PULLDOWN) - 100,
-       ADC_BUTTON_VALUE(ADC_BUTTONS_MIDDLE_R_PULLDOWN) + 100, 1 + BLEN_KEYPAD_MIDDLE }, // ENTER (1205 ... 1405)
+    { adc_other_button, HAL_ADC_RANGE, 1 + BLEN_KEYPAD_F1     }, // F1
+    { adc_other_button, HAL_ADC_RANGE, 1 + BLEN_KEYPAD_F2     }, // F2
+    { adc_other_button, HAL_ADC_RANGE, 1 + BLEN_KEYPAD_F3     }, // F3
+    {  ADC_BUTTON_VALUE(ADC_BUTTONS_LEFT_R_PULLDOWN)   - adc_button_tolerance,
+       ADC_BUTTON_VALUE(ADC_BUTTONS_LEFT_R_PULLDOWN)   + adc_button_tolerance, 1 + BLEN_KEYPAD_LEFT   }, // LEFT  ( 272 ...  472)
+    {  ADC_BUTTON_VALUE(ADC_BUTTONS_RIGHT_R_PULLDOWN)  - adc_button_tolerance,
+       ADC_BUTTON_VALUE(ADC_BUTTONS_RIGHT_R_PULLDOWN)  + adc_button_tolerance, 1 + BLEN_KEYPAD_RIGHT  }, // RIGHT (1948 ... 2148)
+    {  ADC_BUTTON_VALUE(ADC_BUTTONS_UP_R_PULLDOWN)     - adc_button_tolerance,
+       ADC_BUTTON_VALUE(ADC_BUTTONS_UP_R_PULLDOWN)     + adc_button_tolerance, 1 + BLEN_KEYPAD_UP     }, // UP    ( 618 ...  818)
+    {  ADC_BUTTON_VALUE(ADC_BUTTONS_DOWN_R_PULLDOWN)   - adc_button_tolerance,
+       ADC_BUTTON_VALUE(ADC_BUTTONS_DOWN_R_PULLDOWN)   + adc_button_tolerance, 1 + BLEN_KEYPAD_DOWN   }, // DOWN  (2686 ... 2886)
+    {  ADC_BUTTON_VALUE(ADC_BUTTONS_MIDDLE_R_PULLDOWN) - adc_button_tolerance,
+       ADC_BUTTON_VALUE(ADC_BUTTONS_MIDDLE_R_PULLDOWN) + adc_button_tolerance, 1 + BLEN_KEYPAD_MIDDLE }, // ENTER (1205 ... 1405)
   };
 
   uint8_t get_ADC_keyValue() {
     if (thermalManager.ADCKey_count >= 16) {
-      const uint16_t currentkpADCValue = thermalManager.current_ADCKey_raw << 2;
-      thermalManager.current_ADCKey_raw = 1024;
+      const uint16_t currentkpADCValue = thermalManager.current_ADCKey_raw;
+      thermalManager.current_ADCKey_raw = HAL_ADC_RANGE;
       thermalManager.ADCKey_count = 0;
-      if (currentkpADCValue < 4000)
+      if (currentkpADCValue < adc_other_button)
         for (uint8_t i = 0; i < ADC_KEY_NUM; i++) {
           const uint16_t lo = pgm_read_word(&stADCKeyTable[i].ADCKeyValueMin),
                          hi = pgm_read_word(&stADCKeyTable[i].ADCKeyValueMax);

Marlin/src/module/temperature.cpp

@@ -302,7 +302,7 @@ volatile bool Temperature::temp_meas_ready = false;
 // public:
 
 #if HAS_ADC_BUTTONS
-  uint32_t Temperature::current_ADCKey_raw = 1024;
+  uint32_t Temperature::current_ADCKey_raw = HAL_ADC_RANGE;
   uint8_t Temperature::ADCKey_count = 0;
 #endif
 
@@ -1308,7 +1308,7 @@ void Temperature::manage_heater() {
     }
 
     // maximum adc value .. take into account the over sampling
-    const int adc_max = (THERMISTOR_ADC_RESOLUTION * OVERSAMPLENR) - 1,
+    const int adc_max = MAX_RAW_THERMISTOR_VALUE,
               adc_raw = constrain(raw, 1, adc_max - 1); // constrain to prevent divide-by-zero
 
     const float adc_inverse = (adc_max - adc_raw) - 0.5f,
@@ -2742,7 +2742,7 @@ void Temperature::isr() {
           next_sensor_state = adc_sensor_state; // redo this state
         else if (ADCKey_count < 16) {
           raw_ADCKey_value = HAL_READ_ADC();
-          if (raw_ADCKey_value <= 900) {
+          if (raw_ADCKey_value <= 900UL * HAL_ADC_RANGE / 1024UL) {
             NOMORE(current_ADCKey_raw, raw_ADCKey_value);
             ADCKey_count++;
           }
@@ -2750,7 +2750,7 @@ void Temperature::isr() {
             if (ADCKey_count > 0) ADCKey_count++; else ADCKey_pressed = false;
             if (ADCKey_pressed) {
               ADCKey_count = 0;
-              current_ADCKey_raw = 1024;
+              current_ADCKey_raw = HAL_ADC_RANGE;
             }
           }
         }

Marlin/src/module/temperature.h

@@ -217,7 +217,6 @@ typedef struct { int16_t raw_min, raw_max; } raw_range_t;
 typedef struct { int16_t mintemp, maxtemp; } celsius_range_t;
 typedef struct { int16_t raw_min, raw_max, mintemp, maxtemp; } temp_range_t;
 
-#define THERMISTOR_ADC_RESOLUTION       1024           // 10-bit ADC .. shame to waste 12-bits of resolution on 32-bit
 #define THERMISTOR_ABS_ZERO_C           -273.15f       // bbbbrrrrr cold !
 #define THERMISTOR_RESISTANCE_NOMINAL_C 25.0f          // mmmmm comfortable
 

Marlin/src/module/thermistor/thermistors.h

@@ -23,8 +23,21 @@
 
 #include "../../inc/MarlinConfig.h"
 
-#define OVERSAMPLENR 16
-#define OV(N) int16_t((N) * (OVERSAMPLENR))
+#define THERMISTOR_TABLE_ADC_RESOLUTION 1024
+#define THERMISTOR_TABLE_SCALE (HAL_ADC_RANGE / (THERMISTOR_TABLE_ADC_RESOLUTION))
+#if ENABLED(HAL_ADC_FILTERED)
+  #define OVERSAMPLENR 1
+#else
+  #define OVERSAMPLENR 16
+#endif
+#define MAX_RAW_THERMISTOR_VALUE (HAL_ADC_RANGE * (OVERSAMPLENR) - 1)
+
+// Currently Marlin stores all oversampled ADC values as int16_t, make sure the HAL settings do not overflow 15bit
+#if MAX_RAW_THERMISTOR_VALUE > ((1 << 15) - 1)
+  #error "MAX_RAW_THERMISTOR_VALUE is too large for int16_t. Reduce OVERSAMPLENR or HAL_ADC_RESOLUTION."
+#endif
+
+#define OV(N) int16_t((N) * (OVERSAMPLENR) * (THERMISTOR_TABLE_SCALE))
 
 #define ANY_THERMISTOR_IS(n) (THERMISTOR_HEATER_0 == n || THERMISTOR_HEATER_1 == n || THERMISTOR_HEATER_2 == n || THERMISTOR_HEATER_3 == n || THERMISTOR_HEATER_4 == n || THERMISTOR_HEATER_5 == n || THERMISTORBED == n || THERMISTORCHAMBER == n)
 
@@ -251,74 +264,74 @@ static_assert(
 // For thermocouples the highest temperature results in the highest ADC value
 #ifndef HEATER_0_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_0_USES_THERMISTOR)
-    #define HEATER_0_RAW_HI_TEMP 16383
+    #define HEATER_0_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_0_RAW_LO_TEMP 0
   #else
     #define HEATER_0_RAW_HI_TEMP 0
-    #define HEATER_0_RAW_LO_TEMP 16383
+    #define HEATER_0_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_1_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_1_USES_THERMISTOR)
-    #define HEATER_1_RAW_HI_TEMP 16383
+    #define HEATER_1_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_1_RAW_LO_TEMP 0
   #else
     #define HEATER_1_RAW_HI_TEMP 0
-    #define HEATER_1_RAW_LO_TEMP 16383
+    #define HEATER_1_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_2_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_2_USES_THERMISTOR)
-    #define HEATER_2_RAW_HI_TEMP 16383
+    #define HEATER_2_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_2_RAW_LO_TEMP 0
   #else
     #define HEATER_2_RAW_HI_TEMP 0
-    #define HEATER_2_RAW_LO_TEMP 16383
+    #define HEATER_2_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_3_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_3_USES_THERMISTOR)
-    #define HEATER_3_RAW_HI_TEMP 16383
+    #define HEATER_3_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_3_RAW_LO_TEMP 0
   #else
     #define HEATER_3_RAW_HI_TEMP 0
-    #define HEATER_3_RAW_LO_TEMP 16383
+    #define HEATER_3_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_4_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_4_USES_THERMISTOR)
-    #define HEATER_4_RAW_HI_TEMP 16383
+    #define HEATER_4_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_4_RAW_LO_TEMP 0
   #else
     #define HEATER_4_RAW_HI_TEMP 0
-    #define HEATER_4_RAW_LO_TEMP 16383
+    #define HEATER_4_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_5_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_5_USES_THERMISTOR)
-    #define HEATER_5_RAW_HI_TEMP 16383
+    #define HEATER_5_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_5_RAW_LO_TEMP 0
   #else
     #define HEATER_5_RAW_HI_TEMP 0
-    #define HEATER_5_RAW_LO_TEMP 16383
+    #define HEATER_5_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_BED_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_BED_USES_THERMISTOR)
-    #define HEATER_BED_RAW_HI_TEMP 16383
+    #define HEATER_BED_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_BED_RAW_LO_TEMP 0
   #else
     #define HEATER_BED_RAW_HI_TEMP 0
-    #define HEATER_BED_RAW_LO_TEMP 16383
+    #define HEATER_BED_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif
 #ifndef HEATER_CHAMBER_RAW_HI_TEMP
   #if defined(REVERSE_TEMP_SENSOR_RANGE) || !defined(HEATER_CHAMBER_USES_THERMISTOR)
-    #define HEATER_CHAMBER_RAW_HI_TEMP 16383
+    #define HEATER_CHAMBER_RAW_HI_TEMP MAX_RAW_THERMISTOR_VALUE
     #define HEATER_CHAMBER_RAW_LO_TEMP 0
   #else
     #define HEATER_CHAMBER_RAW_HI_TEMP 0
-    #define HEATER_CHAMBER_RAW_LO_TEMP 16383
+    #define HEATER_CHAMBER_RAW_LO_TEMP MAX_RAW_THERMISTOR_VALUE
   #endif
 #endif