Old EPROM questions again, EPROM Programmer

For some perhaps - at the time, myself, and almost everyone I knew worked for companies with programmers, so it was not a problem. You could also get EPROM programmed at the local shop for a small fee. I also had a bytesaver in my Altair, so I could have bootstrapped up from a 2708 if I'd had to. I didn't program the actual firmware right away - I made a EPROM (at work) with my 6809 monitor program in it, which allowed me to download code into the RAM (normally all used as a data buffer), where I tested and debugged the actual firmware - When I was happy that everything was working correctly, I use the RAM download to program a real EPROM (almost self-booting). If I were doing the same project today, and had absolutely no access to any means of programming the initial EPROM, I would first post in the local groups to see if anyone near me has a programmer, failing that, I would perhaps try this list or other more widespread resources - I'm sure that someone somewhere would be willing to program my monitor (or even a very simple loader would suffice) into that first EPROM for me. All you need is the ability to get code into the device, and you can run from there. I guess what I am saying, is that if you are not prepared to be a little creative, you are probably not well suited to designing/building your own test equipment. On my original programmer (the homebuilt one), the programming voltage was selected by a physical switch - which selected 12.5, 21 or 25v from "taps" on a couple of stacked regulators - not the most elegant solution, but it worked (and continues to work). I supported the 'fast' algotithm on all by the 2732 (which would have required me to flip one of the relays during program/read turnaround). Ah the "good ol days"... Regards, Dave -- dave04a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Vintage computing equipment collector. http://www.parse.com/~ddunfield/museum/index.html