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Altera_Forum
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20 years ago

NIOS PIO Interrupt

Hello all, I am monica from germany.I am using NIOS in cyclone FPGA.I have problem with PIO interrupts. Environment details Quartus Software : version 4.2 build 178 01/19/2005 SJ full ...
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Altera_Forum
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20 years ago

With the level interrupt turned on as long as the hardware line is asserted the interrupt will be asserted. To get out of continuous interrupt processing you would need to disable the interrupt inside the interrupt handler or cause the input to the PIO to no longer be asserted.

This isn't the case with the edge sensitive interrupt because the interrupt cause is transient (only when the input changed state).