olddataman
Experienced Member
In the spring of 1976 I sold some IMSAI 8080s that were included in my initial order from them when I became a dealer in early Feb. 1976. One of them went to a man named John Clarke in Shamburg, IL. (who a little later opened The Data Domain of Shamburg. one of the more successful computer stores started in 1876). John was an engineer from Motorola, and a very nice guy and a smart cookie.
He called me one day to tell me that the 8080 chip in his computer was bad. I said that we wold call IMAI and see if there were an more bad ones around and get a replacement. A day or so later he called me again to tell me that the problem was in the design or prodction of the NEC 8080 chip, because he could prove that under certain instruction sequences one instruction failed and cause calculation errors. I don't remember what instruction it was, but he was right and NEC had to redo their maskand replace all of the 8080s made up to that time. So, if you have an early IMSAI and it has a NEC chip you might have a rare one indeed! One of these days I'll look him up again and ask him for details.
He called me one day to tell me that the 8080 chip in his computer was bad. I said that we wold call IMAI and see if there were an more bad ones around and get a replacement. A day or so later he called me again to tell me that the problem was in the design or prodction of the NEC 8080 chip, because he could prove that under certain instruction sequences one instruction failed and cause calculation errors. I don't remember what instruction it was, but he was right and NEC had to redo their maskand replace all of the 8080s made up to that time. So, if you have an early IMSAI and it has a NEC chip you might have a rare one indeed! One of these days I'll look him up again and ask him for details.