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Improvement of timer initialization for pwmout

pull/1289/head
bcostm 2015-08-11 14:42:15 +02:00
parent 8f6a11530c
commit 2b1b1acce6
1 changed files with 28 additions and 17 deletions
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45
libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F7/pwmout_api.c
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@ -42,24 +42,21 @@ void pwmout_init(pwmout_t* obj, PinName pin)
{
// Get the peripheral name from the pin and assign it to the object
obj->pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM);
MBED_ASSERT(obj->pwm != (PWMName)NC);
// Get the functions (timer channel, (non)inverted) from the pin and assign it to the object
uint32_t function = pinmap_function(pin, PinMap_PWM);
MBED_ASSERT(function != (uint32_t)NC);
obj->channel = STM_PIN_CHANNEL(function);
obj->channel = STM_PIN_CHANNEL(function);
obj->inverted = STM_PIN_INVERTED(function);
if (obj->pwm == (PWMName)NC) {
error("PWM error: pinout mapping failed.");
}
// Enable TIM clock
if (obj->pwm == PWM_1) __HAL_RCC_TIM1_CLK_ENABLE();
if (obj->pwm == PWM_2) __HAL_RCC_TIM2_CLK_ENABLE();
if (obj->pwm == PWM_3) __HAL_RCC_TIM3_CLK_ENABLE();
if (obj->pwm == PWM_4) __HAL_RCC_TIM4_CLK_ENABLE();
if (obj->pwm == PWM_8) __HAL_RCC_TIM8_CLK_ENABLE();
if (obj->pwm == PWM_9) __HAL_RCC_TIM9_CLK_ENABLE();
if (obj->pwm == PWM_1) __HAL_RCC_TIM1_CLK_ENABLE();
if (obj->pwm == PWM_2) __HAL_RCC_TIM2_CLK_ENABLE();
if (obj->pwm == PWM_3) __HAL_RCC_TIM3_CLK_ENABLE();
if (obj->pwm == PWM_4) __HAL_RCC_TIM4_CLK_ENABLE();
if (obj->pwm == PWM_8) __HAL_RCC_TIM8_CLK_ENABLE();
if (obj->pwm == PWM_9) __HAL_RCC_TIM9_CLK_ENABLE();
if (obj->pwm == PWM_10) __HAL_RCC_TIM10_CLK_ENABLE();
if (obj->pwm == PWM_11) __HAL_RCC_TIM11_CLK_ENABLE();
if (obj->pwm == PWM_12) __HAL_RCC_TIM12_CLK_ENABLE();
@ -124,7 +121,7 @@ void pwmout_write(pwmout_t* obj, float value)
}
if (HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, channel) != HAL_OK) {
error("Cannot configure PWM channel");
error("Cannot configure PWM channel\n");
}
if (obj->inverted) {
@ -156,14 +153,21 @@ void pwmout_period_ms(pwmout_t* obj, int ms)
void pwmout_period_us(pwmout_t* obj, int us)
{
TimHandle.Instance = (TIM_TypeDef *)(obj->pwm);
RCC_ClkInitTypeDef RCC_ClkInitStruct;
uint32_t PclkFreq;
uint32_t APBxCLKDivider;
float dc = pwmout_read(obj);
__HAL_TIM_DISABLE(&TimHandle);
// Get the PCLK used by the timer
// Get clock configuration
// Note: PclkFreq contains here the Latency (not used after)
HAL_RCC_GetClockConfig(&RCC_ClkInitStruct, &PclkFreq);
// Get the PCLK and APBCLK divider related to the timer
switch (obj->pwm) {
// APB1 clock
case PWM_2:
case PWM_3:
case PWM_4:
@ -172,26 +176,33 @@ void pwmout_period_us(pwmout_t* obj, int us)
case PWM_13:
case PWM_14:
PclkFreq = HAL_RCC_GetPCLK1Freq();
APBxCLKDivider = RCC_ClkInitStruct.APB1CLKDivider;
break;
// APB2 clock
case PWM_1:
case PWM_8:
case PWM_9:
case PWM_10:
case PWM_11:
PclkFreq = HAL_RCC_GetPCLK2Freq();
APBxCLKDivider = RCC_ClkInitStruct.APB2CLKDivider;
break;
default:
return;
}
TimHandle.Init.Period = us - 1;
// TIMxCLK = 2 x PCLKx when the APB prescaler is not equal to 1 (DIV4 or DIV2 in our case)
TimHandle.Init.Prescaler = (uint16_t)((PclkFreq * 2) / 1000000) - 1; // 1 us tick
// TIMxCLK = PCLKx when the APB prescaler = 1 else TIMxCLK = 2 * PCLKx
if (APBxCLKDivider == RCC_HCLK_DIV1)
TimHandle.Init.Prescaler = (uint16_t)((PclkFreq) / 1000000) - 1; // 1 µs tick
else
TimHandle.Init.Prescaler = (uint16_t)((PclkFreq * 2) / 1000000) - 1; // 1 µs tick
TimHandle.Init.ClockDivision = 0;
TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
if (HAL_TIM_PWM_Init(&TimHandle) != HAL_OK) {
error("Cannot initialize PWM");
error("Cannot initialize PWM\n");
}
// Set duty cycle again