how to configure multi click in keypad

[ilham M]

hi every one

i have keypad with 12 buttons(1-9 ,#,*)

so

i need to read character from user

i think the idea is by making a short time loop for each input from the keypad for example 1sec. The purpose of the loop to count how many times you clicks the button within the 1 sec. if you click just once then it gives you a character for example (a) . if you press it twice then it gives you another character (b).


but i dont know how program it

any help plzzz