Merge pull request #4082 from PaoloTK/fix_esp32c3_pwm_bit_depth

Fix incorrect PWM bit depth on Esp32 with XTAL clock
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Blaž Kristan 2024-08-04 17:10:21 +02:00 committed by GitHub
commit d2401a212a
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@ -378,18 +378,41 @@ void BusDigital::cleanup() {
}
#ifdef ESP8266
// 1 MHz clock
#define CLOCK_FREQUENCY 1000000UL
#else
// Use XTAL clock if possible to avoid timer frequency error when setting APB clock < 80 Mhz
// https://github.com/espressif/arduino-esp32/blob/2.0.2/cores/esp32/esp32-hal-ledc.c
#ifdef SOC_LEDC_SUPPORT_XTAL_CLOCK
#define CLOCK_FREQUENCY 40000000UL
#else
#define CLOCK_FREQUENCY 80000000UL
#endif
#endif
#ifdef ESP8266
#define MAX_BIT_WIDTH 10
#else
#ifdef SOC_LEDC_TIMER_BIT_WIDE_NUM
// C6/H2/P4: 20 bit, S2/S3/C2/C3: 14 bit
#define MAX_BIT_WIDTH SOC_LEDC_TIMER_BIT_WIDE_NUM
#else
// ESP32: 20 bit (but in reality we would never go beyond 16 bit as the frequency would be to low)
#define MAX_BIT_WIDTH 20
#endif
#endif
BusPwm::BusPwm(BusConfig &bc)
: Bus(bc.type, bc.start, bc.autoWhite, 1, bc.reversed)
{
if (!IS_PWM(bc.type)) return;
unsigned numPins = NUM_PWM_PINS(bc.type);
_frequency = bc.frequency ? bc.frequency : WLED_PWM_FREQ;
// duty cycle resolution (_depth) can be extracted from this formula: CLOCK_FREQUENCY > _frequency * 2^_depth
for (_depth = MAX_BIT_WIDTH; _depth > 8; _depth--) if (((CLOCK_FREQUENCY/_frequency) >> _depth) > 0) break;
#ifdef ESP8266
// duty cycle resolution (_depth) can be extracted from this formula: 1MHz > _frequency * 2^_depth
if (_frequency > 1760) _depth = 8;
else if (_frequency > 880) _depth = 9;
else _depth = 10; // WLED_PWM_FREQ <= 880Hz
analogWriteRange((1<<_depth)-1);
analogWriteFreq(_frequency);
#else
@ -397,11 +420,6 @@ BusPwm::BusPwm(BusConfig &bc)
if (_ledcStart == 255) { //no more free LEDC channels
deallocatePins(); return;
}
// duty cycle resolution (_depth) can be extracted from this formula: 80MHz > _frequency * 2^_depth
if (_frequency > 78124) _depth = 9;
else if (_frequency > 39062) _depth = 10;
else if (_frequency > 19531) _depth = 11;
else _depth = 12; // WLED_PWM_FREQ <= 19531Hz
#endif
for (unsigned i = 0; i < numPins; i++) {
@ -419,7 +437,7 @@ BusPwm::BusPwm(BusConfig &bc)
}
_data = _pwmdata; // avoid malloc() and use stack
_valid = true;
DEBUG_PRINTF_P(PSTR("%successfully inited PWM strip with type %u and pins %u,%u,%u,%u,%u\n"), _valid?"S":"Uns", bc.type, _pins[0], _pins[1], _pins[2], _pins[3], _pins[4]);
DEBUG_PRINTF_P(PSTR("%successfully inited PWM strip with type %u, frequency %u, bit depth %u and pins %u,%u,%u,%u,%u\n"), _valid?"S":"Uns", bc.type, _frequency, _depth, _pins[0], _pins[1], _pins[2], _pins[3], _pins[4]);
}
void BusPwm::setPixelColor(uint16_t pix, uint32_t c) {