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Altera_Forum
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14 years ago

push_button irq handler question

Hi, I use NEEK CycloneIII (CP3C25). App is quite simple it turns on the led corresponding the push button pressed (see code below). I copied irq handler procedure from standard binary_counter.c ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Tried to display increment. That's what i got.

1. If I put usleep before IOWR_ALTERA_AVALON_PIO_EDGE_CAP(BUTTON_PIO_BASE, 0); it is incremented twice per button push.

2. If I put usleep after clearing function it is incremented once per button push.

So i conclude the delay after clearing edge_capture reg is necessary.