2708 Programming Algorithm?

It's been a long time, but since I just recently handled the old 8748 doc that has the reference I thought I saw, it'll be cleared up soon. I just remember that all the 87xx parts, 8741, 8755, 8748/49, etc, were all 5-volt parts. further, I'm not at all sure that the 8080 had below-ground signal levels, since they were intended to be attached to bipolar parts, e.g. 8212, etc, which would have been intolerant of that. What I've got in my lap is the 8080A data, which may, actually be different, but IIRC, the 8080 needed the negative bias supply so it could swing to ground and the +12 so it could swing to a reasonable high level. My only contact with the 8080 was on boards made by Intel, and, while I poked around with a 'scope and other gear from time to time, I don't recall ever finding an address, data, or control signal that wasn't TTL compatible.