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Altera_Forum's avatar
Altera_Forum
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13 years ago

having trouble with interrupt

Hello everyone , I'm try for a very long time to do a simple interrupt with nios ii. this is my problem: i have button in sratix ii dev kit and all i want to do in nios is just to turn on ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Add these before alt_irq_register:

IOWR_ALTERA_AVALON_PIO_IRQ_MASK(button_IRQ, <irq_bit_mask>); // enable irq

IOWR_ALTERA_AVALON_PIO_EDGE_CAP(button_IRQ, <irq_bit_mask>); // clear irq

You also need to clear the edge capture bit in irq handler function, otherwise the irq will keep on retriggering.

Also make sure of these points:

- in qsys/sopc button pio must be defined with interrupt capability enabled

- the button pio is correctly routed to fpga pin and pio is working: begin with polling the pio in while loop to test this point.