cctalk Digest, Vol 110, Issue 64 - test-drb@ccmp.vtda.org

26 Oct 2012

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  Date: Thu, 25 Oct 2012 13:32:09 -0600
 From: Kevin Reynolds <tpresence at hotmail.com>
 To: <cctech at classiccmp.org>
 Subject: RE: Microvax II won't boot, hardware error?
 Message-ID: <BLU157-W48E7D604E2D698A86B3819A27F0 at phx.gbl>
 Content-Type: text/plain; charset="iso-8859-1"

 I do have multiple memory modules, there are two in the chassis.  I have spare modules,
but they aren't the same, so I am not sure they will work in the system.

 I did pull and replace the CPU, Memory and VCB02 modules, but the result is the same. 
The system did work fine recently, so I assume that the CSR/Vectors are ok on the cards. 
I don't have the manuals for everything, but maybe bitsavers does.

 I don't have any spare grant continuity cards...will this cause me trouble if I just
pull a ramcard out and have nothing in its slot?  I seem to remember that you couldn't
have an open slot between cards, unless you had a grant card in there...

 Is there a standard VMS memory test I can run in conversational mode?
    It actually runs a simple memory test during the power-up diagnostics, I 
think maybe
it was 7...8 that is the memory diags.  They are the ones that takes the 
longest to run,
the others complete mostly in less than a second.

You have to know the layout of your backplane to know where grant contnuity
cards are required.  Old uVax II backplanes have the memory bus on the CD
rows for 2 or 4 slots, and need no grant continuity there, but the AB 
rows are Q-bus, and would
need either double-wide Q-bus boards there or grant continuity. Later 
backplanes
didn't have the Q-bus start until after the first couple slots.  So, you 
really need to know what
the backplane layout is.

Jon