Re: strange 2001N fault

From: Gerrit Heitsch <gerrit_at_laosinh.s.bawue.de>
Date: Wed, 21 Feb 2018 17:37:48 +0100
Message-ID: <05cffab6-6d42-798c-9693-673ee5d45a31@laosinh.s.bawue.de>
On 02/20/2018 11:21 PM, Francesco Messineo wrote:
> 
> Yes, but thinking about it, a refresh failure would maybe not produce
> almost the same values each 128 bytes (I don't really know anyway,
> just guessing that it would just "zero" the bits more randomly).

No. As I wrote before, an empty cell (meaning one that doesn't get 
refreshed) is not always read as '0'. It depends on the RAM maker and 
what kind of pattern they used.


>> There is afaik some test programs that you can burn onto an eprom
>> and run. (I assume that you already know this, though).
> 
> the usual pettester.bin ran for hours without finding RAM errors, but
> that's not really a great test, it completely writes one bank (0),
> then reads it back.

... and refreshes the RAM while it's doing so. Every RAS-cycle is also a 
refresh cycle.

  Gerrit


       Message was sent through the cbm-hackers mailing list
Received on 2018-02-21 17:01:13

Archive generated by hypermail 2.2.0.