Looking for info on National Semiconductor RAM board (VAX 11/730)

Ethan Dicks ethan.dicks at gmail.com
Sun Jun 21 11:32:36 CDT 2015

On Sat, Jun 20, 2015 at 10:58 AM, tony duell <ard at p850ug1.demon.co.uk> wrote:
>> I am looking for any information on a National Semiconductor RAM board that I think goes in
>> a VAX 11/730.

>  Pressing the
> button turns off the yellow LED and completely disables the board. Quite why you'd want to do this I do
> not know...

The reason you'd want a button to disable the board is when running
diagnostics, you can "remove all the non-DEC memory" without
physically removing it.  Of course it still could be the source of a
problem, but at least operational memory boards can be "deleted" so
they don't grossly affect the diagnostic code.

It's a "feature" to allow customers to buy less-expensive RAM and
still have a way to pass diagnostics without fingerpointing from DEC
about that "other" board in there.


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