In Code warrior write a short code fragment to continually read bits 0 and 1 of Port A and turn on bit 0 of Port B if they are different (feel free to reuse any old code you have, or just write a short lookup table to do this). At the same time, the microcontroller should monitor a sensor attached to the IRQ pin and immediately stop processing and light a warning light at bit 0 of Port J if the bit goes low. You should initially clear the bit in the main program.