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Altera_Forum
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12 years ago

Cyclone V GPIO interrupt can not work under low level-trigger mode

Hi all, I'm using Altera Cyclone V board (Board Info http://www.altera.com/products/devkits/altera/kit-cyclone-v-soc.html ). And tried to set User Push Button [0 :3] as low level trigger mode, ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

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What clock frequency and clock divider settings do you use for the GPIO? In order for the edge to propogate to the interrupt logic the button active period would need to be at least 2 debounce clocks in width.

*Sorry I just read the post again and I had it backwards, I thought you said the level interrupts worked but the edge interrupts were not. I agree with what dsl said, your finger is probably still on the button when the ISR completes and you end up re-entering the ISR again. *

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Thanks BadOmen!