Xref: utzoo unix-pc.general:2272 comp.sys.att:5581
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!cbmvax!ditto
From: ditto@cbmvax.UUCP (Michael "Ford" Ditto)
Newsgroups: unix-pc.general,comp.sys.att
Subject: Re: NMI Parity Errors while Parallel Printing
Summary: Mine does it too
Keywords: unixpc panic during printing
Message-ID: <6011@cbmvax.UUCP>
Date: 19 Feb 89 21:21:39 GMT
References: <788@rush.cts.com>
Reply-To: ditto@cbmvax.UUCP (Michael "Ford" Ditto)
Organization: Commodore Technology, West Chester, PA
Lines: 30

In article <788@rush.cts.com> bob@rush.cts.com (Bob Ames) writes:
>We've got a 3B1 which panics with NMI parity errors after 2-10 lines
>have printed through the parallel Port.

Have you tried the same printer & cable on another Unix PC?

My 3B1  has always done the same thing; I'm glad to hear I'm not the only
one, since that seems to point to a cabling problem or something.  Since I
only discovered the problem after the warrantee expired, I just resigned
myself to sending files to the Amiga for printing.  But now, I'll
investigate it further.

I suspect a bug in the lp device driver which only shows up under some rare
timing conditions which our printers somehow make happen.  The one I tried
is an Epson FX-85, with a "straight-through" cable with every pin connected.

>I developed a theory that somehow the parallel port drains some power
>and causes memory to forget.  I'll probably get 20 letters from people
>telling me how silly this theory is.  |-)

Hmmmm... doesn't seem too likely unless you have a marginal ram chip to
start with.  Also, I would expect that just having the printer connected
would be enough to cause such a problem, even if it wasn't printing.
-- 
					-=] Ford [=-

"The number of Unix installations	(In Real Life:  Mike Ditto)
has grown to 10, with more expected."	ford@kenobi.cts.com
- The Unix Programmer's Manual,		...!sdcsvax!crash!kenobi!ford
  2nd Edition, June, 1972.		ditto@cbmvax.commodore.com