Output compare to turn on a LED

[SGROU.1]

Hello,

I am working on a STM32F723E-Disco,

I am learning the use of timers and their functionalities.

In particular, I try to use the output compare.

What I'm trying to do is to use the output compare to turn on a LED when the output compare is triggered.

I don't know where to start, I don't see any examples of what I want to do on the internet.

Do you have any examples, help please?

Thanks

[KnarfB]

There are samples included in the firmware. windoes location: %USERPROFILE%\STM32Cube\Repository\STM32Cube_FW_F7_V1.16.0\Projects\STM32F746ZG-Nucleo\Examples\TIM, alsoavail. online. Not precisely for your board, bt close.

hth

KnarfB

[Ozone]

Be sure to compare the LED current requirement with the limits of the GPIO pin you intend use for driving it.

[SGROU.1]

Thanks for your answers.

I looked at the samples provided by STM32, having also STM32F429, I used it for my tests. It helped me a lot, I think I succeeded.

However, I have a second question,

is it possible that when the output compare is triggered, the PIN of the timer of my channel goes directly to the LED?

Because for the moment, I have configured the TIMER channels directly on the LED PIN.

On my STM429, I can't select any timer going to my LED pin (attached image), how can I make the channel timer corresponding to my output compare to be linked to this pin ?

I don't know if you see what I want to do, I hope so.

Thanks you,

[KnarfB]

If you leave the LED pins (PG13 PG14) in the Reset_State (no Output) you may safely connect a wire from the timer channel output pin to the LED pin to make the LED blinking.

If you don't like wires and timing is not very critical, you can enable a timer OC interrupt and toggle the LED from the interrupt handler in software.

Note that OC is only a short pulse (unless you use Toggle on Match mode). You may also look into PWM mode for dimming a LED.

[SGROU.1]

To be honest, I don't really like wires.

So if I want to turn on the LED by the software, I put my LED in GPIO_OUTPUT.

Then in my output compare callback function : "HAL_TIM_OC_DelayElapsedCallback", I check if the channel of my timer is equal to HAL_TIM_ACTIVE_CHANNEL_X, if it returns true, it enters my condition and turns on my LED.

That's how I see the program, but this one doesn't work, is there something I didn't understand?

void HAL_TIM_OC_DelayElapsedCallback(TIM_HandleTypeDef *htim){
 
	if(htim->Channel == HAL_TIM_ACTIVE_CHANNEL_1){
		HAL_GPIO_WritePin(LD3_GPIO_Port, LD3_Pin, GPIO_PIN_SET);
	}
}

Yes I use the toggle on match mode.

Yes I have already succeeded for dimming a led with the PWM mode.