stm8s timer 1 delay_STM8 timer achieves precise delay (blocking)

Timer selection:

The stm8 timer is slightly different from the stm32 timer. The stm32 timer is 24 bits - 16,777,216. According to the 72M clock divided by 8, the period is about 1.86s, while the stm8 timer is 16/8 - 65535/255, and its own clock is 16M. Even with the 16-division period, it is much less than 1s.

Currently, the TIM2 timer is selected, with a division ratio of 1 and a maximum period of 65536/16, which is approximately equal to 4096us.

initialization

void TIM_Delay_Init()

{

/* The auto-reload value range is 0~255 for TIM4 and 0~65535 for TIM2*/

TIM2_TimeBaseInit(TIM2_PRESCALER_1,65535); //65535*(1/16)≈4095us

TIM2_Cmd(DISABLE); //Disable the timer

}

Delay function

It is best to use register operations in delay functions to reduce the amount of calculations and reduce errors.

void TIM_Delay_us(uint16_t nus)

{

uint16_t value = nus*16;

TIM2->CNTRH = 0; //calculated value cleared

TIM2->CNTRL = 0;

TIM2->CR1 |= (uint8_t)TIM2_CR1_CEN; //Start timing

while(TIM2_GetCounter() < value)

{

/*if(TIM2_GetFlagStatus(TIM2_FLAG_UPDATE)) //The maximum delay time for a single us is reached

{

TIM2_ClearFlag(TIM2_FLAG_UPDATE);

break;

}*/

};

TIM2->CR1 &= (uint8_t)(~TIM2_CR1_CEN); //Stop timing

}

Conclusion

When an 8-bit timer (TIM4) is selected, the one-division period is 16us, the two-division period is 32us, and in the case of ms delay, 5/10/20us can be used as the delay period to implement functions such as Delay_10us() and Delay_N_10us().