I had post a same message before. Timer0 scan a 3*4's keypad with 10mS Interval,and var Key will be changed to a value when button be pressed or 0xff when all buttons be unprssed.Every button include 4 letters,like,one button has '1','a','b','c'and another has '2','d','e','f'. How i can realize these as a keypad on mobilephone,as press button '1' once Key == '1',and double press it quickly Key == 'a',etc?can you give me some source code for exsample? Best regards, Nanntiangumo
basic keypad code (assuping you drive columns and read rows. 1) feed all columns, if no row,: no key 2) scan columns till row active = key found 3) at exit if now_key is not = prev_key ignore 4) if 2 identical reads and result different from last key presented present key. Erik