Filament Width Sensor singleton (#15191)

Marlin/src/feature/filwidth.cpp

@@ -26,11 +26,24 @@
 
 #include "filwidth.h"
 
-bool filament_sensor; // = false;                             // M405/M406 turns filament sensor control ON/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
-uint8_t meas_delay_cm = MEASUREMENT_DELAY_CM;                 // Distance delay setting
-int8_t measurement_delay[MAX_MEASUREMENT_DELAY + 1],          // Ring buffer to delayed measurement. Store extruder factor after subtracting 100
-       filwidth_delay_index[2] = { 0, -1 };                   // Indexes into ring buffer
+FilamentWidthSensor filwidth;
+
+bool FilamentWidthSensor::enabled; // = false;                          // (M405-M406) Filament Width Sensor ON/OFF.
+uint32_t FilamentWidthSensor::accum; // = 0                             // ADC accumulator
+uint16_t FilamentWidthSensor::raw; // = 0                               // Measured filament diameter - one extruder only
+float FilamentWidthSensor::nominal_mm = DEFAULT_NOMINAL_FILAMENT_DIA,   // (M104) Nominal filament width
+      FilamentWidthSensor::measured_mm = DEFAULT_MEASURED_FILAMENT_DIA, // Measured filament diameter
+      FilamentWidthSensor::e_count = 0,
+      FilamentWidthSensor::delay_dist = 0;
+uint8_t FilamentWidthSensor::meas_delay_cm = MEASUREMENT_DELAY_CM;      // Distance delay setting
+int8_t FilamentWidthSensor::ratios[MAX_MEASUREMENT_DELAY + 1],          // Ring buffer to delay measurement. (Extruder factor minus 100)
+       FilamentWidthSensor::index_r,                                    // Indexes into ring buffer
+       FilamentWidthSensor::index_w;
+
+void FilamentWidthSensor::init() {
+  const int8_t ratio = sample_to_size_ratio();
+  for (uint8_t i = 0; i < COUNT(ratios); ++i) ratios[i] = ratio;
+  index_r = index_w = 0;
+}
 
 #endif // FILAMENT_WIDTH_SENSOR

Marlin/src/feature/filwidth.h

@@ -22,10 +22,98 @@
 #pragma once
 
 #include "../inc/MarlinConfig.h"
+#include "../module/planner.h"
 
-extern bool filament_sensor;                                // M405/M406 turns filament sensor control ON/OFF.
-extern float filament_width_nominal,                        // Nominal filament width. Change with M404.
-             filament_width_meas;                           // Measured filament diameter
-extern uint8_t meas_delay_cm;                               // Distance delay setting
-extern int8_t measurement_delay[MAX_MEASUREMENT_DELAY + 1], // Ring buffer to delayed measurement. Store extruder factor after subtracting 100
-              filwidth_delay_index[2];                      // Indexes into ring buffer
+class FilamentWidthSensor {
+public:
+  static constexpr int MMD_CM = MAX_MEASUREMENT_DELAY + 1, MMD_MM = MMD_CM * 10;
+  static bool enabled;              // (M405-M406) Filament Width Sensor ON/OFF.
+  static uint32_t accum;            // ADC accumulator
+  static uint16_t raw;              // Measured filament diameter - one extruder only
+  static float nominal_mm,          // (M104) Nominal filament width
+               measured_mm,         // Measured filament diameter
+               e_count, delay_dist;
+  static uint8_t meas_delay_cm;     // Distance delay setting
+  static int8_t ratios[MMD_CM],     // Ring buffer to delay measurement. (Extruder factor minus 100)
+                index_r, index_w;   // Indexes into ring buffer
+
+  FilamentWidthSensor() { init(); }
+  static void init();
+
+  static inline void enable(const bool ena) { enabled = ena; }
+
+  static inline void set_delay_cm(const uint8_t cm) {
+    meas_delay_cm = _MIN(cm, MAX_MEASUREMENT_DELAY);
+  }
+
+  /**
+   * Convert Filament Width (mm) to an extrusion ratio
+   * and reduce to an 8 bit value.
+   *
+   * A nominal width of 1.75 and measured width of 1.73
+   * gives (100 * 1.75 / 1.73) for a ratio of 101 and
+   * a return value of 1.
+   */
+  static int8_t sample_to_size_ratio() {
+    return ABS(nominal_mm - measured_mm) <= FILWIDTH_ERROR_MARGIN
+           ? int(100.0f * nominal_mm / measured_mm) - 100 : 0;
+  }
+
+  // Apply a single ADC reading to the raw value
+  static void accumulate(const uint16_t adc) {
+    if (adc > 102)  // Ignore ADC under 0.5 volts
+      accum += (uint32_t(adc) << 7) - (accum >> 7);
+  }
+
+  // Convert raw measurement to mm
+  static inline float raw_to_mm(const uint16_t v) { return v * 5.0f * (1.0f / 16383.0f); }
+  static inline float raw_to_mm() { return raw_to_mm(raw); }
+
+  // A scaled reading is ready
+  // Divide to get to 0-16384 range since we used 1/128 IIR filter approach
+  static inline void reading_ready() { raw = accum >> 10; }
+
+  // Update mm from the raw measurement
+  static inline void update_measured_mm() { measured_mm = raw_to_mm(); }
+
+  // Update ring buffer used to delay filament measurements
+  static inline void advance_e(const float &e_move) {
+
+    // Increment counters with the E distance
+    e_count += e_move;
+    delay_dist += e_move;
+
+    // Only get new measurements on forward E movement
+    if (!UNEAR_ZERO(e_count)) {
+
+      // Loop the delay distance counter (modulus by the mm length)
+      while (delay_dist >= MMD_MM) delay_dist -= MMD_MM;
+
+      // Convert into an index (cm) into the measurement array
+      index_r = int8_t(delay_dist * 0.1f);
+
+      // If the ring buffer is not full...
+      if (index_r != index_w) {
+        e_count = 0;                            // Reset the E movement counter
+        const int8_t meas_sample = sample_to_size_ratio();
+        do {
+          if (++index_w >= MMD_CM) index_w = 0; // The next unused slot
+          ratios[index_w] = meas_sample;        // Store the measurement
+        } while (index_r != index_w);           // More slots to fill?
+      }
+    }
+  }
+
+  // Dynamically set the volumetric multiplier based on the delayed width measurement.
+  static inline void update_volumetric() {
+    if (enabled) {
+      int8_t read_index = index_r - meas_delay_cm;
+      if (read_index < 0) read_index += MMD_CM; // Loop around buffer if needed
+      LIMIT(read_index, 0, MAX_MEASUREMENT_DELAY);
+      planner.apply_filament_width_sensor(ratios[read_index]);
+    }
+  }
+
+};
+
+extern FilamentWidthSensor filwidth;

Marlin/src/gcode/feature/filwidth/M404-M407.cpp

@@ -34,12 +34,12 @@
  * M404: Display or set (in current units) the nominal filament width (3mm, 1.75mm ) W<3.0>
  */
 void GcodeSuite::M404() {
-  if (parser.seen('W')) {
-    filament_width_nominal = parser.value_linear_units();
-    planner.volumetric_area_nominal = CIRCLE_AREA(filament_width_nominal * 0.5);
+  if (parser.seenval('W')) {
+    filwidth.nominal_mm = parser.value_linear_units();
+    planner.volumetric_area_nominal = CIRCLE_AREA(filwidth.nominal_mm * 0.5);
   }
   else
-    SERIAL_ECHOLNPAIR("Filament dia (nominal mm):", filament_width_nominal);
+    SERIAL_ECHOLNPAIR("Filament dia (nominal mm):", filwidth.nominal_mm);
 }
 
 /**
@@ -48,28 +48,17 @@ void GcodeSuite::M404() {
 void GcodeSuite::M405() {
   // This is technically a linear measurement, but since it's quantized to centimeters and is a different
   // unit than everything else, it uses parser.value_byte() instead of parser.value_linear_units().
-  if (parser.seen('D')) {
-    meas_delay_cm = parser.value_byte();
-    NOMORE(meas_delay_cm, MAX_MEASUREMENT_DELAY);
-  }
-
-  if (filwidth_delay_index[1] == -1) { // Initialize the ring buffer if not done since startup
-    const int8_t temp_ratio = thermalManager.widthFil_to_size_ratio();
-
-    for (uint8_t i = 0; i < COUNT(measurement_delay); ++i)
-      measurement_delay[i] = temp_ratio;
-
-    filwidth_delay_index[0] = filwidth_delay_index[1] = 0;
-  }
+  if (parser.seenval('D'))
+    filwidth.set_delay_cm(parser.value_byte());
 
-  filament_sensor = true;
+  filwidth.enable(true);
 }
 
 /**
  * M406: Turn off filament sensor for control
  */
 void GcodeSuite::M406() {
-  filament_sensor = false;
+  filwidth.enable(false);
   planner.calculate_volumetric_multipliers();   // Restore correct 'volumetric_multiplier' value
 }
 
@@ -77,7 +66,7 @@ void GcodeSuite::M406() {
  * M407: Get measured filament diameter on serial output
  */
 void GcodeSuite::M407() {
-  SERIAL_ECHOLNPAIR("Filament dia (measured mm):", filament_width_meas);
+  SERIAL_ECHOLNPAIR("Filament dia (measured mm):", filwidth.measured_mm);
 }
 
 #endif // FILAMENT_WIDTH_SENSOR

Marlin/src/lcd/HD44780/ultralcd_HD44780.cpp

@@ -622,14 +622,9 @@ void MarlinUI::draw_status_message(const bool blink) {
     // Alternate Status message and Filament display
     if (ELAPSED(millis(), next_filament_display)) {
       lcd_put_u8str_P(PSTR("Dia "));
-      lcd_put_u8str(ftostr12ns(filament_width_meas));
+      lcd_put_u8str(ftostr12ns(filwidth.measured_mm));
       lcd_put_u8str_P(PSTR(" V"));
-      lcd_put_u8str(i16tostr3(100.0 * (
-          parser.volumetric_enabled
-            ? planner.volumetric_area_nominal / planner.volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]
-            : planner.volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]
-        )
-      ));
+      lcd_put_u8str(i16tostr3(planner.volumetric_percent(parser.volumetric_enabled)));
       lcd_put_wchar('%');
       return;
     }

Marlin/src/lcd/dogm/status_screen_DOGM.cpp

@@ -349,13 +349,8 @@ void MarlinUI::draw_status_screen() {
     strcpy(ystring, ftostr4sign(LOGICAL_Y_POSITION(current_position[Y_AXIS])));
     strcpy(zstring, ftostr52sp( LOGICAL_Z_POSITION(current_position[Z_AXIS])));
     #if ENABLED(FILAMENT_LCD_DISPLAY)
-      strcpy(wstring, ftostr12ns(filament_width_meas));
-      strcpy(mstring, i16tostr3(100.0 * (
-          parser.volumetric_enabled
-            ? planner.volumetric_area_nominal / planner.volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]
-            : planner.volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]
-        )
-      ));
+      strcpy(wstring, ftostr12ns(filwidth.measured_mm));
+      strcpy(mstring, i16tostr3(planner.volumetric_percent(parser.volumetric_enabled)));
     #endif
   }
 

Marlin/src/module/planner.cpp

@@ -1328,14 +1328,14 @@ void Planner::check_axes_activity() {
    * into a volumetric multiplier. Conversion differs when using
    * linear extrusion vs volumetric extrusion.
    */
-  void Planner::calculate_volumetric_for_width_sensor(const int8_t encoded_ratio) {
+  void Planner::apply_filament_width_sensor(const int8_t encoded_ratio) {
     // Reconstitute the nominal/measured ratio
     const float nom_meas_ratio = 1 + 0.01f * encoded_ratio,
                 ratio_2 = sq(nom_meas_ratio);
 
     volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM] = parser.volumetric_enabled
-      ? ratio_2 / CIRCLE_AREA(filament_width_nominal * 0.5f) // Volumetric uses a true volumetric multiplier
-      : ratio_2;                                             // Linear squares the ratio, which scales the volume
+      ? ratio_2 / CIRCLE_AREA(filwidth.nominal_mm * 0.5f) // Volumetric uses a true volumetric multiplier
+      : ratio_2;                                          // Linear squares the ratio, which scales the volume
 
     refresh_e_factor(FILAMENT_SENSOR_EXTRUDER_NUM);
   }
@@ -2069,37 +2069,8 @@ bool Planner::_populate_block(block_t * const block, bool split_move,
   block->nominal_rate = CEIL(block->step_event_count * inverse_secs); // (step/sec) Always > 0
 
   #if ENABLED(FILAMENT_WIDTH_SENSOR)
-    static float filwidth_e_count = 0, filwidth_delay_dist = 0;
-
-    //FMM update ring buffer used for delay with filament measurements
-    if (extruder == FILAMENT_SENSOR_EXTRUDER_NUM && filwidth_delay_index[1] >= 0) {  //only for extruder with filament sensor and if ring buffer is initialized
-
-      constexpr int MMD_CM = MAX_MEASUREMENT_DELAY + 1, MMD_MM = MMD_CM * 10;
-
-      // increment counters with next move in e axis
-      filwidth_e_count += delta_mm[E_AXIS];
-      filwidth_delay_dist += delta_mm[E_AXIS];
-
-      // Only get new measurements on forward E movement
-      if (!UNEAR_ZERO(filwidth_e_count)) {
-
-        // Loop the delay distance counter (modulus by the mm length)
-        while (filwidth_delay_dist >= MMD_MM) filwidth_delay_dist -= MMD_MM;
-
-        // Convert into an index into the measurement array
-        filwidth_delay_index[0] = int8_t(filwidth_delay_dist * 0.1f);
-
-        // If the index has changed (must have gone forward)...
-        if (filwidth_delay_index[0] != filwidth_delay_index[1]) {
-          filwidth_e_count = 0; // Reset the E movement counter
-          const int8_t meas_sample = thermalManager.widthFil_to_size_ratio();
-          do {
-            filwidth_delay_index[1] = (filwidth_delay_index[1] + 1) % MMD_CM; // The next unused slot
-            measurement_delay[filwidth_delay_index[1]] = meas_sample;         // Store the measurement
-          } while (filwidth_delay_index[0] != filwidth_delay_index[1]);       // More slots to fill?
-        }
-      }
-    }
+    if (extruder == FILAMENT_SENSOR_EXTRUDER_NUM)   // Only for extruder with filament sensor
+      filwidth.advance_e(delta_mm[E_AXIS]);
   #endif
 
   // Calculate and limit speed in mm/sec for each axis

Marlin/src/module/planner.h

@@ -375,7 +375,14 @@ class Planner {
     static void calculate_volumetric_multipliers();
 
     #if ENABLED(FILAMENT_WIDTH_SENSOR)
-      void calculate_volumetric_for_width_sensor(const int8_t encoded_ratio);
+      void apply_filament_width_sensor(const int8_t encoded_ratio);
+
+      static inline float volumetric_percent(const bool vol) {
+        return 100.0f * (vol
+            ? volumetric_area_nominal / volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]
+            : volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]
+        );
+      }
     #endif
 
     #if DISABLED(NO_VOLUMETRICS)

Marlin/src/module/temperature.cpp

@@ -301,10 +301,6 @@ volatile bool Temperature::temp_meas_ready = false;
   millis_t Temperature::preheat_end_time[HOTENDS] = { 0 };
 #endif
 
-#if ENABLED(FILAMENT_WIDTH_SENSOR)
-  int8_t Temperature::meas_shift_index;  // Index of a delayed sample in buffer
-#endif
-
 #if HAS_AUTO_FAN
   millis_t Temperature::next_auto_fan_check_ms = 0;
 #endif
@@ -314,10 +310,6 @@ volatile bool Temperature::temp_meas_ready = false;
           Temperature::soft_pwm_count_fan[FAN_COUNT];
 #endif
 
-#if ENABLED(FILAMENT_WIDTH_SENSOR)
-  uint16_t Temperature::current_raw_filwidth = 0; // Measured filament diameter - one extruder only
-#endif
-
 #if ENABLED(PROBING_HEATERS_OFF)
   bool Temperature::paused;
 #endif
@@ -1082,16 +1074,11 @@ void Temperature::manage_heater() {
 
   #if ENABLED(FILAMENT_WIDTH_SENSOR)
     /**
-     * Filament Width Sensor dynamically sets the volumetric multiplier
-     * based on a delayed measurement of the filament diameter.
+     * Dynamically set the volumetric multiplier based
+     * on the delayed Filament Width measurement.
      */
-    if (filament_sensor) {
-      meas_shift_index = filwidth_delay_index[0] - meas_delay_cm;
-      if (meas_shift_index < 0) meas_shift_index += MAX_MEASUREMENT_DELAY + 1;  //loop around buffer if needed
-      LIMIT(meas_shift_index, 0, MAX_MEASUREMENT_DELAY);
-      planner.calculate_volumetric_for_width_sensor(measurement_delay[meas_shift_index]);
-    }
-  #endif // FILAMENT_WIDTH_SENSOR
+    filwidth.update_volumetric();
+  #endif
 
   #if HAS_HEATED_BED
 
@@ -1526,7 +1513,7 @@ void Temperature::updateTemperaturesFromRawValues() {
     redundant_temperature = analog_to_celsius_hotend(redundant_temperature_raw, 1);
   #endif
   #if ENABLED(FILAMENT_WIDTH_SENSOR)
-    filament_width_meas = analog_to_mm_fil_width();
+    filwidth.update_measured_mm();
   #endif
 
   #if ENABLED(USE_WATCHDOG)
@@ -1537,30 +1524,6 @@ void Temperature::updateTemperaturesFromRawValues() {
   temp_meas_ready = false;
 }
 
-
-#if ENABLED(FILAMENT_WIDTH_SENSOR)
-
-  // Convert raw Filament Width to millimeters
-  float Temperature::analog_to_mm_fil_width() {
-    return current_raw_filwidth * 5.0f * (1.0f / 16383.0f);
-  }
-
-  /**
-   * Convert Filament Width (mm) to a simple ratio
-   * and reduce to an 8 bit value.
-   *
-   * A nominal width of 1.75 and measured width of 1.73
-   * gives (100 * 1.75 / 1.73) for a ratio of 101 and
-   * a return value of 1.
-   */
-  int8_t Temperature::widthFil_to_size_ratio() {
-    if (ABS(filament_width_nominal - filament_width_meas) <= FILWIDTH_ERROR_MARGIN)
-      return int(100.0f * filament_width_nominal / filament_width_meas) - 100;
-    return 0;
-  }
-
-#endif
-
 #if MAX6675_SEPARATE_SPI
   SPIclass<MAX6675_DO_PIN, MOSI_PIN, MAX6675_SCK_PIN> max6675_spi;
 #endif
@@ -2241,10 +2204,6 @@ void Temperature::set_current_temp_raw() {
   temp_meas_ready = true;
 }
 
-#if ENABLED(FILAMENT_WIDTH_SENSOR)
-  uint32_t raw_filwidth_value; // = 0
-#endif
-
 void Temperature::readings_ready() {
 
   // Update the raw values if they've been read. Else we could be updating them during reading.
@@ -2252,7 +2211,7 @@ void Temperature::readings_ready() {
 
   // Filament Sensor - can be read any time since IIR filtering is used
   #if ENABLED(FILAMENT_WIDTH_SENSOR)
-    current_raw_filwidth = raw_filwidth_value >> 10;  // Divide to get to 0-16384 range since we used 1/128 IIR filter approach
+    filwidth.reading_ready();
   #endif
 
   #if HOTENDS
@@ -2781,10 +2740,8 @@ void Temperature::isr() {
       case Measure_FILWIDTH:
         if (!HAL_ADC_READY())
           next_sensor_state = adc_sensor_state; // redo this state
-        else if (HAL_READ_ADC() > 102) { // Make sure ADC is reading > 0.5 volts, otherwise don't read.
-          raw_filwidth_value -= raw_filwidth_value >> 7; // Subtract 1/128th of the raw_filwidth_value
-          raw_filwidth_value += uint32_t(HAL_READ_ADC()) << 7; // Add new ADC reading, scaled by 128
-        }
+        else
+          filwidth.accumulate(HAL_READ_ADC());
       break;
     #endif
 

Marlin/src/module/temperature.h

@@ -392,18 +392,10 @@ class Temperature {
       static millis_t preheat_end_time[HOTENDS];
     #endif
 
-    #if ENABLED(FILAMENT_WIDTH_SENSOR)
-      static int8_t meas_shift_index;  // Index of a delayed sample in buffer
-    #endif
-
     #if HAS_AUTO_FAN
       static millis_t next_auto_fan_check_ms;
     #endif
 
-    #if ENABLED(FILAMENT_WIDTH_SENSOR)
-      static uint16_t current_raw_filwidth; // Measured filament diameter - one extruder only
-    #endif
-
     #if ENABLED(PROBING_HEATERS_OFF)
       static bool paused;
     #endif
@@ -570,12 +562,6 @@ class Temperature {
       #define is_preheating(n) (false)
     #endif
 
-    #if ENABLED(FILAMENT_WIDTH_SENSOR)
-      static float analog_to_mm_fil_width();         // Convert raw Filament Width to millimeters
-      static int8_t widthFil_to_size_ratio(); // Convert Filament Width (mm) to an extrusion ratio
-    #endif
-
-
     //high level conversion routines, for use outside of temperature.cpp
     //inline so that there is no performance decrease.
     //deg=degreeCelsius