Francois said: I was speaking about the "regular" cartridges. I really don't have any interest in the Demo carts because they are so popular. I do have a prototype of football but that came with some other carts. Phil Clayton said: I have one. Not because I found it, but because it was given to me. Other than that I have not seen another. I wish I have the time to put up nice pictures like this. Great page. other applications, however the RCA 1802 microprocessor..... I did get a chance to do some F8 programming about 1982 at AMF's Electronics Research Lab. I had to modify the code in a rowing machine. They added a clip for the ear lobe that measured your heart rate. I used a 3870 because I could try out new code by inserting a new EPROM on to the processor. I did burn out one of the 3870s and I stuck a white ceramic 1702 on top and made it into a tie clip to remind me. That was the only processor I have every destroyed. And I still have it today. As for the instruction set, the only thing I remember is that the ACC was always trashed on a return from subroutine. I think the processor use it to pull the return address from the stack. What was the question? ========================================= Doug Coward Press Start Inc. Sunnyvale,CA =========================================