Example for GPIO interrupt.
What is shown in this example:
 1. How to enable gpio interrupt.
 2. How to get count of interrupt.  
 3. How to get interrupt signal.
 4. How to get mask of interrupt. 


Support software version "M502 GPIO Driver Ver 1.04 Loaded" and hardware version "m502 V03" .
 
Support signal of gpio interrupt and response time up to 25ns.

The interrupt Only Support gpio pin 0 ~ 14 . 

2011/07/13 Artila Ace Yang