From: stewart at serissa.com (Lawrence Stewart)
Subject: [COFF] non-volatile main memory (NVMM)
Date: Thu, 20 Feb 2020 18:14:08 -0500 [thread overview]
Message-ID: <460C6BAE-85E4-4040-A538-3C995EC4DB10@serissa.com> (raw)
In-Reply-To: <alpine.BSF.2.21.9999.2002210735410.1121@aneurin.horsfall.org>
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
> _______________________________________________
> COFF mailing list
> COFF at minnie.tuhs.org
> https://minnie.tuhs.org/cgi-bin/mailman/listinfo/coff
prev parent reply other threads:[~2020-02-20 23:14 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-20 11:54 gdmr
2020-02-20 13:31 ` david
2020-02-20 20:39 ` dave
2020-02-20 23:14 ` stewart [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=460C6BAE-85E4-4040-A538-3C995EC4DB10@serissa.com \
--to=coff@minnie.tuhs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).