Ecternal interupt occurs 2 times?

[Arman Ilmak]

Posted on February 19, 2018 at 22:58

Hello guys.

I've started working with stm32f217zg series and i have a problem with external interupt.

I have programmed the mcu and after i push the button the interupt occurs two times instead of one.

I use cube mx to generate the code.

I attached the code so you can see it.

[henry.dick]

Posted on February 21, 2018 at 12:45

There are much better ways to debouncing than to put a big fat delay routine in the isr, of all places.

[AvaTar]

Posted on February 21, 2018 at 13:36

Agree, delays inside of interrupt handlers, especially of this magnitude, tend to be deadly for serious applications.

There are other, better ways to prevent EXTI from generating switch transition events.

[henry.dick]

Posted on February 21, 2018 at 13:55

I wouldn't be too quick to declare a success. Your earlier posts suggested that the readings are always two times of what it should be . Switch bounces are fairly random and it is hard to imagine them being so consistent.

As to debouncing strategies, the best way to debounce is not having to debounce. I have done my fair share of software debounces and I can tell you from experience that no software debounces beats out a small capacitor for simplicity and effectiveness and robustness.