[COFF] non-volatile main memory (NVMM)

[Lawrence Stewart]

So at the old MIT Architecture Machine (predecessor of the Media lab) circa 1975/6 we had Interdata 7/32 
minicomputers running the home-grown Magic 6 OS.

These machines had core memory, and there was a microcode bug that under certain circumstances (happily rare) you could get into an infinite loop taking interrupts or faults of some sort.

Due to the core, this condition could not be cleared by the reset switch or even turning off the power.  IIRC the only way to clear it was to unplug the core memory board while the power was on.

-Larry

> On 2020, Feb 20, at 3:39 PM, Dave Horsfall <dave at horsfall.org> wrote:
> 
> On Thu, 20 Feb 2020, George Ross wrote:
> 
>> We used to regularly restart machines which had been turned off for a while, and they would happily pick up where they left off.  One PDP-8 was happy to resume after several years of idleness.
> 
> There was a story posted to Usenet yonks ago about a minicomputer (PDP-8?) being used for nuclear testing.  The last test involved the box inside a truck, parked on top of the hole.  Truck flies up into the air, but the core memory survived intact, was retrieved, and plugged into another box and all the data read out.  Try doing *that* with solid-state memory :-)
> 
> -- Dave
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