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Set STM32 timer prescaler based on timer clock frequency #388

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Merged
merged 2 commits into from
Apr 19, 2024
Merged

Set STM32 timer prescaler based on timer clock frequency #388

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dec7abf
added code to set timer prescalers and overflow based on actual timer…
Copper280z Mar 11, 2024
f2b7b22
comment out HT->refresh() call
Copper280z Mar 11, 2024
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45 changes: 43 additions & 2 deletions src/drivers/hardware_specific/stm32/stm32_mcu.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -26,7 +26,15 @@ PinMap* timerPinsUsed[SIMPLEFOC_STM32_MAX_PINTIMERSUSED];



bool _getPwmState(void* params) {
// assume timers are synchronized and that there's at least one timer
HardwareTimer* pHT = ((STM32DriverParams*)params)->timers[0];
TIM_HandleTypeDef* htim = pHT->getHandle();

bool dir = __HAL_TIM_IS_TIM_COUNTING_DOWN(htim);

return dir;
}


// setting pwm to hardware pin - instead analogWrite()
Expand Down Expand Up @@ -230,7 +238,7 @@ int _getInternalSourceTrigger(HardwareTimer* master, HardwareTimer* slave) { //
#endif
return -1;
}
#elif defined(STM32F4xx) || defined(STM32F1xx) || defined(STM32L4xx)
#elif defined(STM32F4xx) || defined(STM32F1xx) || defined(STM32L4xx) || defined(STM32F7xx)

// function finds the appropriate timer source trigger for the master/slave timer combination
// returns -1 if no trigger source is found
Expand Down Expand Up @@ -303,6 +311,30 @@ int _getInternalSourceTrigger(HardwareTimer* master, HardwareTimer* slave) {
}
#endif

void syncTimerFrequency(long pwm_frequency, HardwareTimer *timers[], uint8_t num_timers) {
uint32_t max_frequency = 0;
uint32_t min_frequency = UINT32_MAX;
for (size_t i=0; i<num_timers; i++) {
uint32_t freq = timers[i]->getTimerClkFreq();
if (freq > max_frequency) {
max_frequency = freq;
} else if (freq < min_frequency) {
min_frequency = freq;
}
}
if (max_frequency==min_frequency) return;
uint32_t overflow_value = min_frequency/pwm_frequency;
for (size_t i=0; i<num_timers; i++) {
uint32_t prescale_factor = timers[i]->getTimerClkFreq()/min_frequency;
#ifdef SIMPLEFOC_DEBUG
SIMPLEFOC_DEBUG("STM32-DRV: Setting prescale to ", (float)prescale_factor);
SIMPLEFOC_DEBUG("STM32-DRV: Setting Overflow to ", (float)overflow_value);
#endif
timers[i]->setPrescaleFactor(prescale_factor);
timers[i]->setOverflow(overflow_value,TICK_FORMAT);
timers[i]->refresh();
}
}

void _alignTimersNew() {
int numTimers = 0;
Expand Down Expand Up @@ -382,7 +414,7 @@ void _alignTimersNew() {
// enable timer clock
for (int i=0; i<numTimers; i++) {
timers[i]->pause();
//timers[i]->refresh();
// timers[i]->refresh();
#ifdef SIMPLEFOC_STM32_DEBUG
SIMPLEFOC_DEBUG("STM32-DRV: Restarting timer ", getTimerNumber(get_timer_index(timers[i]->getHandle()->Instance)));
#endif
Expand Down Expand Up @@ -735,6 +767,8 @@ void* _configure2PWM(long pwm_frequency, const int pinA, const int pinB) {

HardwareTimer* HT1 = _initPinPWM(pwm_frequency, pinTimers[0]);
HardwareTimer* HT2 = _initPinPWM(pwm_frequency, pinTimers[1]);
HardwareTimer *timers[2] = {HT1, HT2};
syncTimerFrequency(pwm_frequency, timers, 2);
// allign the timers
_alignPWMTimers(HT1, HT2, HT2);

Expand Down Expand Up @@ -779,6 +813,9 @@ void* _configure3PWM(long pwm_frequency,const int pinA, const int pinB, const in
HardwareTimer* HT2 = _initPinPWM(pwm_frequency, pinTimers[1]);
HardwareTimer* HT3 = _initPinPWM(pwm_frequency, pinTimers[2]);

HardwareTimer *timers[3] = {HT1, HT2, HT3};
syncTimerFrequency(pwm_frequency, timers, 3);

uint32_t channel1 = STM_PIN_CHANNEL(pinTimers[0]->function);
uint32_t channel2 = STM_PIN_CHANNEL(pinTimers[1]->function);
uint32_t channel3 = STM_PIN_CHANNEL(pinTimers[2]->function);
Expand Down Expand Up @@ -821,6 +858,8 @@ void* _configure4PWM(long pwm_frequency,const int pinA, const int pinB, const in
HardwareTimer* HT2 = _initPinPWM(pwm_frequency, pinTimers[1]);
HardwareTimer* HT3 = _initPinPWM(pwm_frequency, pinTimers[2]);
HardwareTimer* HT4 = _initPinPWM(pwm_frequency, pinTimers[3]);
HardwareTimer *timers[4] = {HT1, HT2, HT3, HT4};
syncTimerFrequency(pwm_frequency, timers, 4);
// allign the timers
_alignPWMTimers(HT1, HT2, HT3, HT4);

Expand Down Expand Up @@ -918,6 +957,8 @@ void* _configure6PWM(long pwm_frequency, float dead_zone, const int pinA_h, cons
HardwareTimer* HT4 = _initPinPWMLow(pwm_frequency, pinTimers[3]);
HardwareTimer* HT5 = _initPinPWMHigh(pwm_frequency, pinTimers[4]);
HardwareTimer* HT6 = _initPinPWMLow(pwm_frequency, pinTimers[5]);
HardwareTimer *timers[6] = {HT1, HT2, HT3, HT4, HT5, HT6};
syncTimerFrequency(pwm_frequency, timers, 6);
uint32_t channel1 = STM_PIN_CHANNEL(pinTimers[0]->function);
uint32_t channel2 = STM_PIN_CHANNEL(pinTimers[1]->function);
uint32_t channel3 = STM_PIN_CHANNEL(pinTimers[2]->function);
Expand Down
3 changes: 3 additions & 0 deletions src/drivers/hardware_specific/stm32/stm32_mcu.h
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Original file line number Diff line number Diff line change
Expand Up @@ -28,5 +28,8 @@ typedef struct STM32DriverParams {
void _stopTimers(HardwareTimer **timers_to_stop, int timer_num=6);
void _startTimers(HardwareTimer **timers_to_start, int timer_num=6);

// timer query functions
bool _getPwmState(void* params);

#endif
#endif