RS232 keypad with autorepeat and 2 key rollover. [Deleted]

This project uses a 12F508 (or 12F509) to read a keypad and send the results over RS232. It is most useful as an add-on to other pic projects that require some way to input numbers. This keypad acts the same way as your PC keyboard in that when a key is held down, it has the short delay before it repeats the key. Both the delay and repeat speed are settable in software just like your PC keyboard.

Many people will wonder what "2 key rollover" means. The best answer is with a little...

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