On Wed, Feb 21, 2018 at 12:33 AM, Mia Magnusson <mia@plea.se> wrote: > > This is a far call and highly unlikely, but could there be a bad joint > where both sides of the pcb connects? I.e. some power rail crossing > broken so there in fact is power rail bounce but just not visible > unless measured at the right spot on the pcb? it can be very well, this 3032 was stored for years in a damp place, tin on the solder side is still shiny and clean, but component side is a quite bad state. I will try first to identify the bad signal(s) then see what causes them. > >> > 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. Another clue that probably refresh works fine (and >> its address counter does seem to count correctly, as far as I could >> see). > > Maybe it's time to make an updated version :) yes yes... that's on my rather long list.... > > I haven't looked at the schematics, but maybe it asserts RAS for both > banks and then only CAS for the bank that's actually addressed? yes, /RAS is shared and there're separate /CAS for the banks (not really an option here, it must be this way). So the fact that bank1 gets corrupted with only read/refresh activity, means I have to look for some problem in the addresses or multiplexers as it has been suggested. Frank Message was sent through the cbm-hackers mailing listReceived on 2018-02-21 08:00:02
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