STM32_Micro_Second_Delay

Intro :

This project create us-delay with timer Made with STM32CubeMX with STM32CubeIDE Toolchain Selected microcontroller is STM32F4xx and HAL library has been used. (for other microcontrollers, just repalce library)

Clock configuration :

Clock configured 168MHz with PLL (maximum for my microcontroller,you can use any clock-rate):

Create Project :

TIM1 settings:

Just set clock source, internal clock

PSC set at 167 ((Used-Clock/1,000,000)-1) and counter period at maximum Value.

attention: for other Used-Clock, just modify PSC.

Code algorithm :

Algorithm is so simple:

First start the timer (in this code, Timer 1),

HAL_TIM_Base_Start(&htim1);

Then reset CNT value,

htim1.Instance->CNT=0;

And wait for CNT to reach us(input) value (with while).

while(htim1.Instance->CNT < us);

Result :

In main function, toggle GPIOE port, pin 15 every 20 micro-second and result:

Notes :

Accuracy :

Result was not exactly 20us because HAL-library functions have a delay itself and if it was very large, you can calibre it manually:

For example if we want 40us delay and every time we got ~42 us, write this code before the while:

us -= 2;

Other method :

Also you can library to make us-delay with HAL-library functions delay rather than Timer.

For example, write this code and monitor the delay and calibre it with changing the value to make one us delay :

void us_delay(int us){
value = 10000;
delay = us * value;
for(int i;i < delay;i++);

}