NorthStar Advantage diagnostic disk wanted - test-drb@ccmp.vtda.org

28 Apr 2005

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Subject: NorthStar Advantage diagnostic disk wanted
   From: "John" <john_a_s2004 at hotmail.com>
   Date: Thu, 28 Apr 2005 09:43:03 +0100
     To: <cctech at classiccmp.org>

Unfortunately GBASIC often crashes with a 'RAM Parity Error' message, I
guess most of the RAM is OK else it wouldn't boot. The Technical Manual
refers to the dealers Diagnostic Diskette, and shows a series of tests to
identify faulty RAM chip. I don't wish to try and re-seat all the chips as
when I tried this on my Pet it has failed to display anything since (another
pending repair project). 
Ther is an easy way.  The NS*dos has a monitor and a memory test.  If the 
memory test isnt there use the monitor.  from the monitor Fill ram with 
a constant of Zeros and display it looking for non zero values.  Do it 
again with ones (FFh) and again display if and look for NON FFh values.
It's not exhaustive but I've found all bad ram that way in the past.

The alternate is that there isn't that much ram and in mine it's 
socketed. So shotgunning though not pretty is possible.

Allison