DEC KA650 VAX memory troubleshooting (video)

[Joe Zatarski]

OK, so where should a thing like this go: https://pastebin.com/taQwaTV6

Anybody got a decent place to upload that? it's my notes on the MS650-AA,
and more generally the KA650 CMCTL memory subsystem.

Includes my theory of operation of the CMCTL, the organization of memory,
the ECC equations (kinda, the info is there to derive them), explanations
of the signals on the memory bus, and most importantly, a list of which
bits and RAM regions correspond to the 312 DRAMs on the board.

On Sat, Jun 15, 2019 at 8:33 PM Joe Zatarski <joezatarski at gmail.com> wrote:
>
> Hey Everyone,
>
> I just thought I'd share a video of how I'm going about troubleshooting
the bad DRAMs on my MS650 memory board.
>
> https://youtu.be/eDMhdAEFEgc
>
> I apologize for the shaky-cam, I don't have a tripod, and I needed to do
a lot of panning anyway.
>
> I will be sharing my notes on the MS650 once I have a chance to write
them up properly as well. I wasn't able to find a printset for the RAM card
itself, so I assume one doesn't exist in digital form yet. I have
documented what bit and memory range each DRAM on the card corresponds to,
which may help someone troubleshooting in the future
>
> Regards,
> Joe Zatarski