Matrix Keypad

Hi All

i want to develop a customized keypad using GPIOs of Beaglebone Black instead of using keyboard

i read previews post regarding keypad but no use. and also i don’t want to use any keypad drivers like

ADP5588,twl4030,and any i2c based keypad driver… i want to develop with GPIO pins of BBB

so if any one have a information or any source regarding this means please share with me

Thanks in Advance

Mallikarjuna G