After seeing our communications via light post , reader [Chris] dropped this handy little link in our inbox. A very good tutorial about using infrared to enable communications between 2 pic micro controllers.

The tutorial covers all the parts you will need, physical wiring and schematics with notes detailing each section of the circuit. It then goes on into basic IR theory, and a simplified push button circuit you can make to see that it is, in fact, working. Once you get the exercise built on some breadboards, he does some software and get some results from it all.

Now in the end this little device was hitting in the neighborhood of 9600 baud, but had to be pretty darn close to each other with a direct line of sight. These  are often accepted as a couple of drawbacks to IR technologies. IR, which has never really vanished, is in use on a lot of devices though. The more you know the better off you are.

Join us after the break for a quick video!

[Mario Mauerer] and friends were commissioned to build this 2m persistence of vision display (translated) for a party (in a hight-voltage lab no less). Dubbed “Display from Hell”, it uses 100 blue SMD LEDs to generate the POV images. They’re connected to an ATMega64 via shift registers. Their target speed is 600rpm for a flicker free image, which means the propeller tips are moving at 140mph. The board can be updated wirelessly via IRDA and plans for adding SD storage are in place. You have to see and HEAR this thing in the video embedded below.