Question
What is correct to update PWM pulse width in STM32F0 HAL?
Posted on April 14, 2018 at 07:52
Hi,
I am trying to learn PWM generation with STM32F030F3P6. Generated code using STM32CubeMX. Basic PWM generation worked fine.
Now I am trying to change PWM pulse width dynamically in while loop of
main()int main(void)
{
uint16_t pwm_value = 0;
uint16_t step = 10;
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_TIM14_Init();
HAL_TIM_PWM_Start(&htim14, TIM_CHANNEL_1);
while (1)
{
HAL_Delay(100);
if(pwm_value = 0) {
step = 50;
}
if(pwm_value >= 1000) {
step = -50;
}
pwm_value += step;
__HAL_TIM_SET_COMPARE(&htim14, TIM_CHANNEL_1, pwm_value);
}
}
�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?Here is full main.c file (most of comments are stripped out).
#include 'main.h'
#include 'stm32f0xx_hal.h'
TIM_HandleTypeDef htim14;
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM14_Init(void);
void HAL_TIM_MspPostInit(TIM_HandleTypeDef *htim);
int main(void)
{
uint16_t pwm_value = 0;
uint16_t step = 10;
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_TIM14_Init();
HAL_TIM_PWM_Start(&htim14, TIM_CHANNEL_1);
while (1)
{
HAL_Delay(100);
if(pwm_value = 0) {
step = 50;
}
if(pwm_value >= 1000) {
step = -50;
}
pwm_value += step;
__HAL_TIM_SET_COMPARE(&htim14, TIM_CHANNEL_1, pwm_value);
}
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;
/**Initializes the CPU, AHB and APB busses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Initializes the CPU, AHB and APB busses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSE;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
/**Configure the Systick interrupt time
*/
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
/**Configure the Systick
*/
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
/* SysTick_IRQn interrupt configuration */
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}
/* TIM14 init function */
static void MX_TIM14_Init(void)
{
TIM_OC_InitTypeDef sConfigOC;
htimInstance = TIM14;
htimInit.Prescaler = 7;
htimInit.CounterMode = TIM_COUNTERMODE_UP;
htimInit.Period = 1000;
htimInit.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htimInit.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&htim14) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
if (HAL_TIM_PWM_Init(&htim14) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_LOW;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
if (HAL_TIM_PWM_ConfigChannel(&htim14, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
HAL_TIM_MspPostInit(&htim14);
}
/** Configure pins as
* Analog
* Input
* Output
* EVENT_OUT
* EXTI
*/
static void MX_GPIO_Init(void)
{
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOF_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
}
void _Error_Handler(char *file, int line)
{
while(1)
{
}
}
�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?PWM generation woks good if I remove code lines within while loop and put any desired value for line:
sConfigOC.Pulse = 0;�?As far as I think, I am not calling __HAL_TIM_SET_COMPARE() right way or something else is required there. Could you please help me to identify that?
Thanks in advance. #stm32-f0 #timer #pwm