Gerardo and I designed the hardware for the I0 receiver.

We did the board & schematic in Eagle. Here are the files:
rcv012a.sch
rcv012a.brd

We printed the circuit board using the etching machine, stuffed it and prayed.

I wrote this simple piece of code and a makefile to program it.
internet0.zip

Plugged it in.......

And it worked. The very first time. : )

Nice blinking LEDs...and off to the software team......