Here's the infrared interface for HaD|Bg badge, which will be exibited and available during the conference. It connects with some desktop PC through RS-232 port, and converts bidirectional serial data signals to infrared, modulated with 40 KHz carrier. There are LEDs which display the current status: red eyes blink each time when it receives bytes from the badge, and the blue hat blinks when PC transmits data via infrared LED.
It will have two functions on the 04.09 happening:
First, everybody will be able to express themselves by entering the name or some other ASCII message in the serial terminal via keyboard, and transfering it to the badge. As the badge is equipped with moving message function, we shall have a hundreds of messages running around.
Second, if you intend to employ the infrared TX/RX during the software hacking workshop, you will be able to test the parts of the program by simply communicating with the desktopćs terminal
In case you wonder about the unusual PCB design - its the leftover of the old project, now equipped with one PIC18F2220 (in the original version, there were two MCUs, but the lower one is empty now). Microcontroller is not too busy - it only generates 40KHz carrier and generates timings for LED blinking during RX or TX. The signal actually doesn't pass through the MCU.