I know how to turn off the annoying water drip sound on the phone keypad but I would like to have the dtmf standard keypad tones when i press the keys.
Does anybody know how to do this?
I have the Keycool 22 USB keypad which has backlit keys.
I have interface keypad (4x4) with PIC16F877 using Hi-tech C compiler.
Now I want to scan the keypad to know that is any key pressed or not???
How can I use timer to scan the keypad so that I did not need to scan the keypad every time in program code???
I think I can use timer to scan the keypad but I dont know how to use it..
Please suggest me....