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Pavel A.
December 17, 2020
Question

EXTI direct input on STM32H7 can be used for level sensitive interrupts?

  • December 17, 2020
  • 4 replies
  • 1963 views

Dear experts,

I'm looking how to achieve level sensitive interrupts with EXTI.

Already found several questions here with discouraging answers.

However, in H7 RM the EXTI chapter mentions some "direct event input" (RM0433 19.3.3)

It looks (though I could not understand from the text) that certain EXTI inputs can be "directly" routed to NVIC, bypassing the edge detector. And this would allow the level sensitive interrupts.

Has anyone done this?

Any comments, please?

Thanks,

Pavel A

This topic has been closed for replies.

4 replies

waclawek.jan
Super User
December 18, 2020

With WAKEUPx pins?

Why don't you simply try?

JW

Pavel A.
Pavel A.Author
December 18, 2020

Jan, because I cannot figure out how to set the EXTI registers for this mode.

Anyway, looks like level sensitive behavior is possible. Will post later.

Regards,

-- pa

Associate
September 14, 2023

@Pavel A.I was wondering if you were able to (fully or partly) achieve this behaviour with the STM32H7 device. We are facing a similar issue, where we need the device to react to level triggered interrupts, but the H7 devices only support edge triggered interrupts. I would be glad if there was a way into / around this issue.

Pavel A.
Pavel A.Author
September 14, 2023

@sammie.k  Please see here: 

https://community.st.com/t5/stm32-mcus-products/level-sensitive-interrupts-with-exti/m-p/202177

This works on H7. I haven't explored EXTI internals since then though it looks promising.