Atari ST diskettes
paulkoning at comcast.net
Mon Dec 7 14:15:18 CST 2020
> On Dec 7, 2020, at 2:50 PM, Van Snyder via cctalk <cctalk at classiccmp.org> wrote:
> One of my friends changed the tables in a 1620 to do octal arithmetic,
> for telemetry processing.
> Speaking of those tables, do you remember why the 1620 was called
> CADET? Not because it was a "beginner's" or "novice" computer. It was
> an acronym for "Can't Add; Doesn't Even Try."
The Model II added hardware add/multiply.
> The Computer History Museum in Mountain View, California has a 1620
> that worked for a time. They had a problem with cooling the core
> memory, which they could probably repair.
Or perhaps heating. I remember that our college 1620 Model II needed a couple of minutes after power-on before it would be willing to operate; supposedly that time was spent waiting for the heaters in the core memory to bring it up to operating temperature.
Apparently timing and/or signal levels in core memory are fairly sensitive to temperature, so keeping them consistent is helpful. It isn't common to select a temperature well above ambient and use heaters to do that, but it isn't totally strange.
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