Ernesto Palacios / FastPWM

Ley de Ohm

Fork of FastPWM by Erik -

Device/FastPWM_STM_TIM.cpp@32:c87e19d668e2, 2017-05-09 (annotated)

Committer:
Yo_Robot
Date:
Tue May 09 16:34:49 2017 +0000
Revision:
32:c87e19d668e2
Parent:
28:3c8a0d977bc3 
modified version do not use

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Sissors 13:cdefd9d75b64 1 //This should (hopefully) work on all STM targets which use TIM timers for PWM
Sissors 13:cdefd9d75b64 2
Sissors 13:cdefd9d75b64 3 #ifdef TARGET_STM
Sissors 13:cdefd9d75b64 4
Sissors 13:cdefd9d75b64 5 #include "FastPWM.h"
Sissors 13:cdefd9d75b64 6
jocis 17:8378bc456f0d 7 typedef __IO uint32_t* CHANNEL_P_T;
jocis 17:8378bc456f0d 8
jocis 17:8378bc456f0d 9 #define PWM_CHANNEL (**(CHANNEL_P_T*)fast_obj)
Sissors 13:cdefd9d75b64 10 #define PWM_TIMER ((TIM_TypeDef*)_pwm.pwm)
Sissors 13:cdefd9d75b64 11
Sissors 28:3c8a0d977bc3 12 #if defined(TARGET_STM32F0) || defined (TARGET_STM32F1) || defined (TARGET_STM32L1)
Sissors 28:3c8a0d977bc3 13 extern __IO uint32_t* getChannel(TIM_TypeDef* pwm, PinName pin);
Sissors 28:3c8a0d977bc3 14 #endif
Sissors 13:cdefd9d75b64 15
Sissors 13:cdefd9d75b64 16 void FastPWM::initFastPWM( void ) {
jocis 17:8378bc456f0d 17 fast_obj = new (CHANNEL_P_T);
Sissors 28:3c8a0d977bc3 18
Sissors 28:3c8a0d977bc3 19 #if defined(TARGET_STM32F0) || defined (TARGET_STM32F1) || defined (TARGET_STM32L1)
jocis 17:8378bc456f0d 20 *(CHANNEL_P_T*)fast_obj = getChannel(PWM_TIMER, _pwm.pin);
Sissors 28:3c8a0d977bc3 21 #else
Sissors 28:3c8a0d977bc3 22 *(CHANNEL_P_T*)fast_obj = &PWM_TIMER->CCR1 + _pwm.channel - 1;
Sissors 28:3c8a0d977bc3 23 #endif
jocis 17:8378bc456f0d 24
Sissors 22:db9c0cf445e2 25 //Enable PWM period syncing for glitch free result
Sissors 22:db9c0cf445e2 26 PWM_TIMER->CR1 |= TIM_CR1_ARPE;
Sissors 22:db9c0cf445e2 27
Sissors 13:cdefd9d75b64 28 bits = 16;
Sissors 13:cdefd9d75b64 29 }
Sissors 13:cdefd9d75b64 30
Sissors 13:cdefd9d75b64 31 void FastPWM::pulsewidth_ticks( uint32_t ticks ) {
Sissors 13:cdefd9d75b64 32 PWM_CHANNEL = ticks;
Sissors 13:cdefd9d75b64 33 }
Sissors 13:cdefd9d75b64 34
Sissors 13:cdefd9d75b64 35 void FastPWM::period_ticks( uint32_t ticks ) {
Sissors 13:cdefd9d75b64 36 PWM_TIMER->ARR = ticks - 1;
Sissors 13:cdefd9d75b64 37 }
Sissors 13:cdefd9d75b64 38
Sissors 13:cdefd9d75b64 39 uint32_t FastPWM::getPeriod( void ) {
Sissors 13:cdefd9d75b64 40 return PWM_TIMER->ARR + 1;
Sissors 13:cdefd9d75b64 41 }
Sissors 13:cdefd9d75b64 42
Sissors 13:cdefd9d75b64 43 uint32_t FastPWM::setPrescaler(uint32_t reqScale) {
Sissors 13:cdefd9d75b64 44 if (reqScale == 0)
Sissors 13:cdefd9d75b64 45 //Return prescaler
Sissors 13:cdefd9d75b64 46 return PWM_TIMER->PSC + 1;
Sissors 13:cdefd9d75b64 47 if (reqScale > (uint32_t)(1<<16))
Sissors 13:cdefd9d75b64 48 reqScale = 1<<16;
Sissors 13:cdefd9d75b64 49 //Else set prescaler, we have to substract one from reqScale since a 0 in PCVAL is prescaler of 1
Sissors 13:cdefd9d75b64 50 PWM_TIMER->PSC = reqScale - 1;
Sissors 13:cdefd9d75b64 51
Sissors 13:cdefd9d75b64 52 return reqScale;
Sissors 13:cdefd9d75b64 53 }
Sissors 13:cdefd9d75b64 54
Sissors 13:cdefd9d75b64 55 #endif