Software Arts, as in Visicalc, used Prime computers. I see from a biography of Dan Bricklin, the less technical of the two, that:
Prior to forming Software Arts, he had been a market researcher for Prime Computer Inc., a senior systems programmer for FasFax Corporation, and a senior software engineer for Digital Equipment Corporation. At Digital, he was project leader of the WPS-8 word processing software, where he helped to specify and develop one of the first standalone word processing systems.
And the more technical partner Bob Frankston was an MIT type. I remember one Software Arts employee, friend of one or more, or maybe Bob's youngest brother, who was a friend of mine, mention that among other things they appreciated what the system adopted from Multics.
Being bit-sliced, the Prime micro-architecture you mention was microcoded, which of course would fit with their following the example of the successful System 360, many models of which had to be microcoded because the logic family they used pretty much had only one speed, they made micro-architectures narrower, down to 8 bits as I recall, for the slower machines, and the 2? fastest had none.
Honeywell's rejection of microcoding helped made Multics and GECOS systems terribly uncompetitive, at least by the time Visicalc was being developed, although the macro-architecture allowed you to easily hook up 6 CPUs in one system (and 8 with a horrible kludge, as I recall).
Prior to forming Software Arts, he had been a market researcher for Prime Computer Inc., a senior systems programmer for FasFax Corporation, and a senior software engineer for Digital Equipment Corporation. At Digital, he was project leader of the WPS-8 word processing software, where he helped to specify and develop one of the first standalone word processing systems.
And the more technical partner Bob Frankston was an MIT type. I remember one Software Arts employee, friend of one or more, or maybe Bob's youngest brother, who was a friend of mine, mention that among other things they appreciated what the system adopted from Multics.
Being bit-sliced, the Prime micro-architecture you mention was microcoded, which of course would fit with their following the example of the successful System 360, many models of which had to be microcoded because the logic family they used pretty much had only one speed, they made micro-architectures narrower, down to 8 bits as I recall, for the slower machines, and the 2? fastest had none.
Honeywell's rejection of microcoding helped made Multics and GECOS systems terribly uncompetitive, at least by the time Visicalc was being developed, although the macro-architecture allowed you to easily hook up 6 CPUs in one system (and 8 with a horrible kludge, as I recall).