Important changes to forums and questions

All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.

Interrupt Pin Issues

Topic last updated 06 Nov 2011, by Gert van der Knokke. 2 replies
Scott Downie
06 Nov 2011

Hello,

I'm a newbie. I'm having trouble with the interrupt pin. I'm trying to perform a function when the interrupt pin goes high. I was under the impression that using pin.mode(PullUp) and pin.mode(PullNone) will pull it up to Vcc or high. However, my mbed doesn't do that. It just stays at the default low value. I tried using digital and AnalogIn just to verify but those don't seem to be pulling high either. Here's basically what i'm doing,

InterruptIn pin(p19);

pin.mode(PullUp); pin.mode(PullNone);

Some function..

I may be using these incorrectly. Any help that can be rendered is much appreciated.

David Fletcher
06 Nov 2011

Olaide,

Try this link http://mbed.org/handbook/DigitalIn Edit: Added And this link http://mbed.org/handbook/InterruptIn

Then post again if you still have problems.

Gert van der Knokke
06 Nov 2011

Quote from the handbook:

Quote:

The InterruptIn interface is used to trigger an event when a digital input pin changes.

Any of the numbered mbed pins can be used as an InterruptIn, except p19 and p20