include bug fix

MarlinFirmware#25337

Marlin/src/HAL/AVR/fast_pwm.cpp

@@ -23,6 +23,10 @@
 
 #include "../../inc/MarlinConfig.h"
 
+//#define DEBUG_AVR_FAST_PWM
+#define DEBUG_OUT ENABLED(DEBUG_AVR_FAST_PWM)
+#include "../../core/debug_out.h"
+
 struct Timer {
  volatile uint8_t* TCCRnQ[3]; // max 3 TCCR registers per timer
  volatile uint16_t* OCRnQ[3]; // max 3 OCR registers per timer
@@ -108,36 +112,47 @@ const Timer get_pwm_timer(const pin_t pin) {
 }
 
 void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
+ DEBUG_ECHOLNPGM("set_pwm_frequency:: pin:",pin," frequency: ",f_desired);
  const Timer timer = get_pwm_timer(pin);
  if (timer.isProtected || !timer.isPWM) return; // Don't proceed if protected timer or not recognized
 
  const bool is_timer2 = timer.n == 2;
  const uint16_t maxtop = is_timer2 ? 0xFF : 0xFFFF;
-
+ DEBUG_ECHOLNPGM("maxtop: ",maxtop);
  uint16_t res = 0xFF; // resolution (TOP value)
  uint8_t j = CS_NONE; // prescaler index
  uint8_t wgm = WGM_PWM_PC_8; // waveform generation mode
 
  // Calculating the prescaler and resolution to use to achieve closest frequency
  if (f_desired != 0) {
  constexpr uint16_t prescaler[] = { 1, 8, (32), 64, (128), 256, 1024 }; // (*) are Timer 2 only
- uint16_t f = (F_CPU) / (2 * 1024 * maxtop) + 1;  // Start with the lowest non-zero frequency achievable (1 or 31)
+ uint16_t f = (F_CPU) / ((uint32_t)maxtop<<11) + 1; // Start with the lowest non-zero frequency achievable (for 16MHz, 1 or 31)
 
+ DEBUG_ECHOLNPGM("F: ",f);
+ DEBUG_ECHOLNPGM("Startloop::");
  LOOP_L_N(i, COUNT(prescaler)) { // Loop through all prescaler values
  const uint16_t p = prescaler[i];
+ DEBUG_ECHOLNPGM("prescaler: ",p);
  uint16_t res_fast_temp, res_pc_temp;
  if (is_timer2) {
+ DEBUG_ECHOLNPGM("Is Timer2::");
  #if ENABLED(USE_OCR2A_AS_TOP) // No resolution calculation for TIMER2 unless enabled USE_OCR2A_AS_TOP
  const uint16_t rft = (F_CPU) / (p * f_desired);
  res_fast_temp = rft - 1;
+ DEBUG_ECHOLNPGM("res_fast_temp: ",res_fast_temp);
  res_pc_temp = rft / 2;
+ DEBUG_ECHOLNPGM("res_pc_temp: ",res_pc_temp);
  #else
  res_fast_temp = res_pc_temp = maxtop;
+ DEBUG_ECHOLNPGM("res_fast_temp: ",maxtop);
+ DEBUG_ECHOLNPGM("res_pc_temp: ",maxtop);
  #endif
  }
  else {
+ DEBUG_ECHOLNPGM("Not Timer2::");
  if (p == 32 || p == 128) continue; // Skip TIMER2 specific prescalers when not TIMER2
  const uint16_t rft = (F_CPU) / (p * f_desired);
+ DEBUG_ECHOLNPGM("F_CPU: ",STRINGIFY(F_CPU)," prescaler: ",p," f_desired: ",f_desired);
  res_fast_temp = rft - 1;
  res_pc_temp = rft / 2;
  }
@@ -146,22 +161,31 @@ void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
  LIMIT(res_pc_temp, 1U, maxtop);
 
  // Calculate frequencies of test prescaler and resolution values
- const uint16_t f_fast_temp = (F_CPU) / (p * (1 + res_fast_temp)),
- f_pc_temp = (F_CPU) / (2 * p * res_pc_temp);
- const int f_diff = _MAX(f, f_desired) - _MIN(f, f_desired),
+ const uint16_t f_fast_temp = (F_CPU) / ((uint32_t)p * (1 + res_fast_temp)),
+ f_pc_temp = (F_CPU) / (((uint32_t)p * res_pc_temp)<<1),
+   f_diff = _MAX(f, f_desired) - _MIN(f, f_desired),
  f_fast_diff = _MAX(f_fast_temp, f_desired) - _MIN(f_fast_temp, f_desired),
  f_pc_diff = _MAX(f_pc_temp, f_desired) - _MIN(f_pc_temp, f_desired);
+ DEBUG_ECHOLNPGM("f_fast_temp: ",f_fast_temp);
+ DEBUG_ECHOLNPGM("f_pc_temp: ",f_pc_temp);
+ DEBUG_ECHOLNPGM("f_diff: ",f_diff);
+ DEBUG_ECHOLNPGM("f_fast_diff: ",f_fast_diff);
+ DEBUG_ECHOLNPGM("f_pc_diff: ",f_pc_diff);
 
  if (f_fast_diff < f_diff && f_fast_diff <= f_pc_diff) { // FAST values are closest to desired f
+ DEBUG_ECHOLNPGM("Using FAST::");
  // Set the Wave Generation Mode to FAST PWM
  wgm = is_timer2 ? uint8_t(TERN(USE_OCR2A_AS_TOP, WGM2_FAST_PWM_OCR2A, WGM2_FAST_PWM)) : uint8_t(WGM_FAST_PWM_ICRn);
  // Remember this combination
  f = f_fast_temp; res = res_fast_temp; j = i + 1;
+ DEBUG_ECHOLNPGM("updated f: ",f);
  }
  else if (f_pc_diff < f_diff) { // PHASE CORRECT values are closes to desired f
+ DEBUG_ECHOLNPGM("Using PHASE::");
  // Set the Wave Generation Mode to PWM PHASE CORRECT
  wgm = is_timer2 ? uint8_t(TERN(USE_OCR2A_AS_TOP, WGM2_PWM_PC_OCR2A, WGM2_PWM_PC)) : uint8_t(WGM_PWM_PC_ICRn);
  f = f_pc_temp; res = res_pc_temp; j = i + 1;
+ DEBUG_ECHOLNPGM("updated f: ",f);
  }
  }
  }
@@ -219,4 +243,4 @@ void MarlinHAL::init_pwm_timers() {
  set_pwm_frequency(pwm_pin[i], 1000);
 }
 
-#endif // __AVR__
+#endif // __AVR__