> On Dec 16, 2015, at 8:08 PM, Alan Frisbie <fris...@flying-disk.com> wrote:
>
> On 12/16/2015 03:51 PM, Will Senn wrote:
>
>> If it doesn't come through imagine a guy with a pair of
> > wire cutters snipping off diodes from a ROM card for a PDP11.
> > Is this really how y'all programmed back in the day :)?
>
> Yep, did that back in the day. Imagine the fun of soldering
> diodes back in to correct a mistake or change the program.
> True, it was usually just a bootstrap, but it was sure a lot
> better than having to toggle it in every time.
The amazing part was that a single 16-word program could boot from a half dozen
different devices.
CDC has a slicker approach: the 6000 series boot ROM ("deadstart panel") was a
matrix of 12 rows of 12 switches. The boot mechanism would use that as the
initial set of instructions, much like the M792 diode ROM you mentioned. But
they were far easier to reprogram!
paul
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