TIMERS used as DELAY Function For Beginners on STM32F3

[projnikdroid]

Posted on December 19, 2013 at 13:28

Function works for TIM6 basic timer used as delay on STM32F303 , with suitable modifications can work on any STM8,32 variants

void TIMER_DELAY(uint16_t value)

{

RCC->APB1ENR |= RCC_APB1Periph;

//value is 0x10

        TIM6->ARR = value;       // delay in ms

TIM6->PSC = 36000-1;  // APB1 = 36Mhz so eqn :  CLK_CNT = (36000000)/36000,i.e. CLK_CNT = 1Khz

TIM6->CR1 = 0x01;         // ENaBle TIMER 

while(!((TIM6->SR & 0x01) == 0x01));  // Check for Update Event

TIM6->CR1 &= ~(0x01);                      // Disable timer

TIM6->SR &= ~(0x01);                        // Reset the update event

}

For eg. TIMER_DELAY(100) would provide me 100ms delay.

#old-school-delay-loops

[Tesla DeLorean]

Posted on December 19, 2013 at 16:06

TIM6->SR = ~(0x01);    // Not RMW

Personally I find DWT_CYCCNT to be far easier, and providing sub-microsecond resolution.

[dthedens23]

Posted on December 19, 2013 at 17:59

I would get laughed out of the office if I were to submit some code for review which had a spin in place delay loop for some number of milliseconds.

The timer peripheral is better off being used as a system resource as a one shot timer where modules can register for a call back.  The module passes a time interval parameter when registering.

[chen]

Posted on December 19, 2013 at 18:19

That is the difference between professional engineers and the amateur!

We should encourage the amateurs to learn better styles of coding.

[projnikdroid]

Posted on December 20, 2013 at 14:07

Dear RocketDawg,

I guess it's very hard for u to read the title, so just to clarify , it was intended only for some basic knowledge.

[projnikdroid]

Posted on December 20, 2013 at 14:09

Dear sung.chen_chung,

FYI coders are not born professionalists(some exceptions)...it always starts from amateurs. And instead of showing criticism ,,, enlighten others