This project is done in Atmel M8535 IC. Here the martix key pad is connected to PORTA. The result is diplaied on LCD connected to PORTC.
For LCD you can refer to my LCD header Files Posted in this site.
PORTA.2 for First column check.
PORTA.1 for Second column check.
PORTA.3 for Third column check.
Except DDRA.0...3, rest of the pins are input.
Hereby i am posting all the files required.....(.asm,.c,.h).