car/my_src/pwm.c

/*
 * pwm.c
 *
 *  Created on: Jan 16, 2018
 *      Author: wn
 */

#include "pwm.h"
#include "stm32f1xx_hal.h"
#include <PontCoopScheduler.h>


extern TIM_HandleTypeDef htim3;


const int32_t PWM_MAX = 10000;
const int32_t PWM_STEP = 200;

typedef struct {
  int32_t value;
  int32_t direction;
} tPwmHandle;

tPwmHandle pwmHandle = { .value = 0, .direction = 1 };

void pwmExec(void *handle) {
  tPwmHandle *lPwmHandle = (tPwmHandle*) handle;
  lPwmHandle->value += (PWM_STEP * lPwmHandle->direction);
  if (lPwmHandle->value >= PWM_MAX) {
    lPwmHandle->direction = -1;
  }
  if (lPwmHandle->value <= 0) {
    lPwmHandle->direction = 1;
  }

  __HAL_TIM_SET_COMPARE(&htim3, TIM_CHANNEL_1, lPwmHandle->value);
}

void pwmInit() {
  schAdd(pwmExec, &pwmHandle, 0, 50);

  __HAL_TIM_SET_AUTORELOAD(&htim3, PWM_MAX);

  __HAL_TIM_SET_COMPARE(&htim3, TIM_CHANNEL_1, 0);
  HAL_TIM_PWM_Start(&htim3, TIM_CHANNEL_1);
}