sbw@naucse.UUCP (Steve Wampler) (04/19/89)
I need some help determining what the memory diagnostics are trying
to tell me about the combo board I just tried to install:
System: 3B1, 2MB on motherboard, UNIX 3.5 diagnostic disk.
I just got a 0K Combo board onto which I placed 1.5MB. Since the
system recognizes that I have 1.5MB, I assume that I at least got
the two jumpers in the right place. However, when running the
memory diagnostics, I get *lots* and *lots* of errors on the
expansion board Address Connection subtest. Briefly put these
messages look like:
Pass 1
Memory Error: Connection to line X bad
Wrote 55 to address Y, wrote FFFFFAA to address Z, read 57 from address Y
Where X is (in repeating sequence) 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,
17,18,21 (Should I at least be grateful it skipped lines 19 & 20?).
And Y is (in sequence) 200000 200002 200004 200008 200010 200020 .... 240000
(After all these error messages, it repeats, with slight variations in
addresses..)
Now, what does it all mean? Since it's an address connection, I tried
to board in different slots: no change in messages. Do I have a *bunch*
of fried memory chips (I *thought* I was well grounded, but...)? Which
ones? Is the logic on the board itself fried? How should I proceed in
tracking down the problem?
I'd be eternally grateful for any explanations/suggestions (well grateful
for most suggestions, anyway)!
Thanks!
--
Steve Wampler
{....!arizona!naucse!sbw}jcs@tarkus.chi.il.us (John C. Sucilla) (04/21/89)
In article <1354@naucse.UUCP> sbw@naucse.UUCP (Steve Wampler) writes: >Memory Error: Connection to line X bad >Wrote 55 to address Y, wrote FFFFFAA to address Z, read 57 from address Y > >Where X is (in repeating sequence) 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16, > 17,18,21 (Should I at least be grateful it skipped lines 19 & 20?). >And Y is (in sequence) 200000 200002 200004 200008 200010 200020 .... 240000 Looks like your combo boards memory is working except bit 1 (one) is stuck active on the data bus. Check for a bent backplane pin. I'll bet you've got data bit one shorted to adress bits 19 and 20. -- "We do what we can, but this little guy called Fate will do what he pleases anyway. All we can do is give him enough to work with and hope it goes the way we want." - S.S.