Interesting thread ... nice reading. For the design of a small 6802-based system check: www.pdp-11.nl/homebrew/startframe.html and click the links "interface hardware" and "interface monitor". The project has had little time lately, but I am working on the mechanical part: a new sleakier front. Anyway, it has the CPU (...), 8 kbytes RAM, 8 kbytes EPROM, and is very easy to expand with as much I/O you want. Hey, if you are going to connect a "PDP-11" console to it (relax chaps, a home-made one, the real consoles stay on my machines!) you need *lots* of I and O. All fits on a single board. I still can write a program in hex opcodes for the 6802. Risk of starting a flame: Motorola is way nicer to work with in assembly language than all the Intel crap. Words hi- and lo-byte swapped ... go figure ! gd lck with your hardware, - Henk, PA8PDP