Help using PC Interrupt

hi..

I am trying to make a Hall effect based speedometer . Instead of using the hardware interrupts on pins 2 and 3 , I intend to use any of the PC [Pin change] Interrupts to detect change in the hall output pin. However I don't know how to code this. Any help in this regard pls...

thanks in advance

http://playground.arduino.cc/Main/PinChangeInt should help

Instead of using the hardware interrupts on pins 2 and 3 , I intend to use any of the PC [Pin change] Interrupts to detect change in the hall output pin.

Why?