You may recall I've posted here in the last couple of months about my college project, which was to make a Connect4 game using 42 LED's, doing display multiplexing so that only one column is lit at a time.
I had a very funky shift-register setup in which I used two precisely- timed RC circuits so that I'd only need one microcontroller pin to control the shifting. The theory was sound, but there was some doubt upon the practicality of it all.
Anyway, in the end it all works perfectly. I've left the device powered on for 48 hours straight and it hasn't malfunctioned. With the twelve microcontroller pins that I had available, I was able to:
- Light the 42 LED's
- Light a "Player LED" which indicates whose go it is
- Light two seven segment displays (one common anode, one common cathode) showing how many goes have gone by.
- Power a Piezo speaker.
And in all it's pretty nifty :-D I might put a video of it up on YouTube at some stage.