lots of panics in uPort V -> Problems @ 10MHz

[Derek E. Terveer]

In article <421 at zap.UUCP>, fortin at zap.UUCP (Denis Fortin) writes:
> In article <829 at ddsw1.UUCP> karl at ddsw1.UUCP (Karl Denninger) writes:
> >In article <115 at hawkmoon.UUCP> det at hawkmoon.UUCP (Derek E. Terveer) writes:
> >>[running SysV/386]  The problem is that
> >>i seem to be having lots of (relatively) unexplainable panics and i was
> >>wondering if anyone else with the 386 version was also having numbers of these
> >>panics, like "kernel mode traps" (type e), "user mode traps" (type 2 and 8),
> >>and "iupdat - iaddress >2^24" panics.  Plus i keep getting a number of "NMI in
> >>system mode" messages.  
> >
> >The key one is the NMI message.
> >
> >This can only be generated one way -- if your memory board(s) generate a
> >parity fault.

When i <det at hawkmoon> posted the original message, above, my machine was not
only in panic mode --> so was i.  I had just spent a not inconsiderable amount
of money on a '386 machine plus the uport software to run on it.  It installed
and then pretty much from day 2 started crashing from 1 to 5 times a day.
Imagine my horror at witnessing these events!  So of course i was worried and
hoped that someone on the net would be able to help.  Karl <karl at ddsw1> was the
one that tipped me off.  He stated that the "NMI in system mode" messages only
happened in this plane of existence when parity errors occurred.  I thought
about it for a
little bit -- there should not have been *ANY* parity errors from the chips
themselves, it was a brand new board and i tested the board and all the chips
for some 70+ times.  I was confident that it couldn't be the board.  Therefore,
drawing on my experience with running some other unix machines (vax 11/780s), i
inspected my environment.  Power?  I had my pc plugged into an outlet with one
of those little-itsy-bitsy noise filters that plug into a two outlet wall
receptacle and provide three somewhat filterd outlets.  I also had my stereo
and a lamp plugged into the same outlet - considering the house is 40+ years
old and they didn't use electricity back then (:-) i only have two outlets in
my room!  I decided to test whether or not the stereo and lamp were somehow
dirtying the power to my pc and moved them to another outlet, courtesy of a
long extension cord.  I ran for a couple of days -- no problems.

I have now run for TWO weeks with not a *single* problem!!!!  Obviously, i was
getting some sort of substandard power with the other stuff plugged in.
Especially upon retrospect i realized that my pc only seemed to crash when my
stereo was on.

So an apology is on order here from me to microport.  They may or may not have
problems, but my PC crashing all the time is now not one of them.  I am very
pleased with the stability of the system now (now if only i had more memory it
would be a little faster (:-)).

Moral of the story:  When you start getting errors like the ones i described
(esp. NMI errors), check the environment and isolate your pc if you can.

Now all i have to do is figure out where to put my damn extension cord
connecting my stereo and lamp.....

> [..]
> I can run the system with no problems at 6MHz, and I can run it at 10MHz
> without any problems under both DOS and IBM XENIX 1.0 (which I don't use
> anymore since I have uPort).  Unfortunately, whenever I attempt to run
> SV/AT at 10MHz, it crashes after a few minutes (sometimes even before that).
> [..]
> In a few cases, I've noticed the message "NMI in system mode" at boot time,
> *but* my 2MB of RAM are all 100ns chips, which *should* be more than 
> sufficient for 10MHz operation!!!

I got the same message within about 5 minutes or less of boot time, but i don't
think it has to do with the speed of the chips.  Karl pointed out that these
are parity errors.  You could run your board diagnostics, if you have any, and
see if there are any problems there.  Also, a lot of times the speed of the
BUS is different than the speed of the cpu/motherboard.  For example, i have a
16MHz cpu, but my bus speed, to which i have attached 2Mb of memory on an intel
above board, is *only* ~8Mhz.  You didn't state your config as far as memory
goes, so if you only need the barest minimum of memory, like 640K, to run
uport, perhaps you could take out the extra memory if its on a seperate board
and see if you can then run uport at 10MHz.  If you can, then theres obviously
a problem with your extra memory.

You suggestion about the graphics board is a valid one, but i don't know enough
about that to comment further.

Finally, check the power.

Hope this helps...!

> (Also, could anybody post a description of what those "user=n" messages
>  mean?

Yes, yes, please!

derek
-- 
Derek Terveer	det at hawkmoon.MN.ORG	uunet!rosevax!elric!hawkmoon!det