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Old 02-16-03, 07:14 PM   #4 (permalink)
commoved
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Join Date: Dec 2002
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It's been so long ... I don't even remember the name. Was it Altair? Or IMSIA? I think they were competitors. It had an S100 bus, an 8080 processor, and you could buy 128 Kbyte memory boards if you had the money. You loaded programs through front panel switches - in octal. Later, there was a cassette loader -- you only had to load the boot program. The big thing was to know how to use the audio casette tapes instead of spending big bucks on the digital tapes, by accounting for the leader.

A year earlier than that, at work, I was using an Intellec 8 MDS to develop 8008 code. The I/O terminal was an ASR33 teletype with paper tape reader/punch. You could load the editor in about 15 minutes, but it took 45 minutes to load the macro-assembler. The only practical way to debug programs was to know the op-codes and hand-edit the object code in memory with a debugger program. I would insert a jump at the errant instruction, write the new code, then jump back. I still remember some of the hex values for the op-codes (JMP = C3). The day we got the high speed tape reader was a big day.

I remember using the 1702A EPROM. I worked for Westinghouse at the time. Another division wanted more memory per chip. So they decided to unpack the 1702As and re-pack them, two to a chip. They had a lot of problems destroying chips in the process. Some VP of R&D got wind of the problems and made an edict that nobody could use 1702As, as they were too unreliable.

My project was going down the tubes because the 8008 didn't have the compute power to do what I needed it to do. Intel saved my ass with the 8080. Then as now, we just needed a little more processing power.
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