Create a precision timer with HAL and interrupt

[matteo239955_st]

Posted on November 20, 2015 at 12:41

Hi guys,

I'm using CubeMx with HAL STM32F051. I need to activate a one shot timer with interrupt.Something likr this:void StartTimer(unsigned short microSecond){ ... ...}volatile unsigned char TimerIsOver = 0; void HAL_TIM_OC_DelayElapsedCallback(TIM_HandleTypeDef *htim) { TimerIsOver = 1;}void main(void) { LedOff(); TimerIsOver = 0; StartTimer(20); while(!TimerIsOver); LedOn(); TimerIsOver = 0; HAL_Delay(50); LedOff(); StartTimer(340); while(!TimerIsOver); LedOn(); } #stm32-hal-tim

[waclawek.jan]

Posted on November 20, 2015 at 19:20

Any question?

[Tesla DeLorean]

Posted on November 20, 2015 at 22:33

For micro-seconds, where you're going to idle in a loop, why not just have that timer free run, and delta the tick count from TIMx->CNT ?

[matteo239955_st]

Posted on November 23, 2015 at 08:18

Please could you write for me StartTimer function?

Thank you very much...

[Tesla DeLorean]

Posted on November 23, 2015 at 15:14

Sorry, I'm not writing HAL examples.

A free running timer would be a matter of configuring the time base in a maximal count mode, in your case probably with a 1us (1MHz) prescaled clock. Read the count at the start of the loop, and delta it over the duration. Interrupting at 1 MHz is NOT viable, so software counters aren't a solution.