WIU and falling edge triggered interrupts

terg · ‎2007-08-01

Posted on August 02, 2007 at 07:20

terg · ‎2011-05-17

Posted on May 17, 2011 at 09:45

This is my first post so I'm hoping someone can help or point me in the right direction!

I have a Hitex ARM STR912 Starter Kit and IAR compiler.

The starter kit has 5 push button switches (which are high when released and low when pressed) which I've configured to generate a VIC1.9 (WIU all) interrupt. The interrupts are configured for falling edge.

In the interrupt service routine for the WIU I've added a simple count++ statement.

The problem I get is this:-

When I press a button, I get an interrupt as expected and 'count' increments. When I release the button I also get an interrupt and 'count' is incremented a second time.

We've scoped the switch input and it looks pretty clean when released.

Whats interesting is if I set the interrupt trigger to rising edge, pushing and releasing the button only generates the one interrupt and it behaves as expected.

Anyone got any thoughts?

terg · ‎2011-05-17

Posted on May 17, 2011 at 09:45

Thanks mirou

I'm using the VIC1.9 (WIU all) as the interrupt source. Will have to do a bit more investigation.

amira1 · ‎2011-05-17

Posted on May 17, 2011 at 09:45

Hello GoSquirrels,

I've tested a code as you described it and I didn't face any problem with WIU interrupt. I work with IAR compiler on the STR9 Eval-Board. You find attached the IAR project.

Are you using another interrupt with WIU interrupt?

With best regards,

mirou