Incorrect interrupt time

[Nmo.1]

Hi everyone,

I'm using Nucleo H723 board. I have used 8 timers in encoder mode to read the encoders. I have also activated another timer to make an interrupt every 4ms to send the data via Usart.

everything work good but when I use sprint code to put the data in Usart, the interrupt time has been changed and it's not 4ms.

Part of my code inside interrupt:

/* USER CODE BEGIN 4 */
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
 
 	timer2 = __HAL_TIM_GET_COUNTER(&htim2);
 	timer5 = __HAL_TIM_GET_COUNTER(&htim5);
 	timer23 = __HAL_TIM_GET_COUNTER(&htim23);
 	timer24 = __HAL_TIM_GET_COUNTER(&htim24);
 	timer1 = __HAL_TIM_GET_COUNTER(&htim1);
 	timer3 = __HAL_TIM_GET_COUNTER(&htim3);
 	timer4 = __HAL_TIM_GET_COUNTER(&htim4);
 	timer8 = __HAL_TIM_GET_COUNTER(&htim8);
 
	 count_FL_1=timer1/4;
	 count_FR_1=timer3/4;
	 count_RR_1=timer5/4;
	 count_RL_1=timer23/4;
 
	 count_FL_2=timer2/4;
	 count_FR_2=timer4/4;
	 count_RR_2=timer8/4;
	 count_RL_2=timer24/4;
 
 
 sprintf(buffer_FL_1, "FL_1: %ld\n", count_FL_1);
	 sprintf(buffer_FR_1, "FR_1: %ld\n", count_FR_1);
	 sprintf(buffer_RR_1, "RR_1: %ld\n", count_RR_1);
	 sprintf(buffer_RL_1, "RL_1: %ld\n", count_RL_1);
	 sprintf(buffer_FL_2, "FL_2: %ld\n", count_FL_2);
	 sprintf(buffer_FR_2, "FR_2: %ld\n", count_FR_2);
	 sprintf(buffer_RR_2, "RR_2: %ld\n", count_RR_2);
	 sprintf(buffer_RL_2, "RL_2: %ld\n", count_RL_2);
 
 
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_i,strlen(buffer_i), 100);
 
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_FL_1,strlen(buffer_FL_1), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_FR_1,strlen(buffer_FR_1), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_RR_1,strlen(buffer_RR_1), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_RL_1,strlen(buffer_RL_1), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_FL_2,strlen(buffer_FL_2), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_FR_2,strlen(buffer_FR_2), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_RR_2,strlen(buffer_RR_2), 100);
	 HAL_UART_Transmit(&huart3, (uint8_t *) buffer_RL_2,strlen(buffer_RL_2), 100);
 
 
 i++;
 j=i/1000;
 
 
 
 
}

Hier is my timer configuration.

when I delete the sprint codes the timer 4ms runs again correctly.

I appreciate it if you help me.

[Peter BENSCH]

sprintf consumes a lot of memory and takes a lot of time.

What about your heap size?

Regards

/Peter

[Nmo.1]

O.K. Thank you so much. I'm a beginner and didn't know that. So I need to try another way to sent data to PC.

How can I find heap size?

[Peter BENSCH]

It looks like you create your skeleton program using STM32CubeMX or the STM32CubeIDE: just open your project > Project Manager, where you can set the heap size and the stack size.

Alternatively you can change it in the file ***_FLASH_ld, but that would be under the level of CubeMX, because it doesn't know about it and overwrites it again when the code is regenerated. The default value there is:

_Min_Heap_Size = 0x200 ; /* required amount of heap */
_Min_Stack_Size = 0x400 ; /* required amount of stack */

Regards

/Peter