i connect row1->p0.0 row2->p0.1 row3->p0.2 row4->p0.3 colum1 ---->p0.4 column2---->p0.5 column3----->p0.5 i pull up all columns with 4.7k to vcc this keypad is telephone keypad please help me to write a program for this best regards javad majd
Take a look at this appnote: http://www.cypressmicro.com/support/appnotes/an2034.pdf Also do a google search for "keyboard debouncing algorithms". - mike