How to make stm32 smart delay before execution?

Question

Microcontrollers

There are such cases, some devices require a delay between different commands, for example, wait 300ms, arduino people are used to simple while(cnt--) loops, but this does not suit me, so the question is how to organize a delay with a timer?
Here is the code I posted:

#include "Delay.h"

static uint8_t flag = 1;

void delay(uint32_t _delay){

  initTIM6();
  TIM6->ARR = _delay;
  TIM6->CR1 |= TIM_CR1_CEN;
  flag = 1;
  while(flag);

}


void TIM6_IRQHandler(void){
  flag = 0;
  TIM6->CR1 &= ~TIM_CR1_CEN;
  TIM6->SR &= ~TIM_SR_UIF;
}

void initTIM6(){
  RCC->APB1ENR |= RCC_APB1ENR_TIM6EN;
  TIM6->PSC = SystemCoreClock / 1000 - 1;
  TIM6->DIER |= TIM_DIER_UIE;
  NVIC_EnableIRQ(TIM6_IRQn);
}

in the right place just call delay(300); but for some reason the delay occurs for a shorter time, but all other functions are working at that moment, that is, it does not seem to take up CPU time. But there is still a problem in that for a delay of 1s I need to enter not 1000 but 10,000, although the limiter is set so that the CNT register is increased every 1000ms

Answer 1

Hmm, prescaler 1000, does it work at 1 MHz in total?