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Altera_Forum's avatar
Altera_Forum
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11 years ago

External interrupt not triggering software exception

I currently hav a push button connected up to my IRQ input on my Nios. When the button is asserted, I expect to see my program counter jump to my exceptions section in my assembly source code. When t...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

If your interrupt pulse is too short NIOS can miss it. The best practice is to set the IRQ high (in RTL), and then reset it in NIOS in the interrupt service routine. So your RTL will also need an avalon slave port to talk to NIOS's data master.