Video card strangeness

[Robert Barrell]

     Recently, the company for which I work replaced a client's Sperry PC/ITE
286 machine with a Mitsubishi MP386 machine.  Since the client needed two
parallel printer ports, they had been using an Emulex monochrome controller
which included a parallel port (the Sperry came with one parallel port already
on the "subsystem" board which also includes two serial ports).  For them to
maintain their two-printer capability, we swapped video cards between the Sperry
and the Mitsubishi (which had the standard, Mitsubishi "UCC" video card).  The
video and print functions of the Emulex board, now within the Sperry, work fine.
The Mitsubishi board within the Sperry, however, is exhibiting strange behavior
under SCO xenix.
     Under DOS, everything is fine.  Under xenix, though, characters are only
displayed until the last screen line is reached.  After that, the cursor will
move as it should, but the characters won't appear.  If I hit return enough
times to get back to the last screen line again, everything that had been
printed "invisibly" earlier, shows up.
     We had experienced this same problem about a year ago, with an Everex
"Graphics Edge" board.  SCO told us that the "Graphics Edge" board would not
work with a monochrome monitor under xenix, but only with a color monitor.
Indeed, when a color monitor was attached, the board worked fine under xenix.
     The Mitsubishi board appears to be working the same way, but IT HAD WORKED
PERFECTLY with a monochrome monitor, when in the Mitsubishi machine.  This leads
me to believe there is either a difference between the machines causing this, or
a difference in the drivers between xenix286 version 2.2.3 and xenix386 version
2.3.1.
     Has anyone experienced a similar problem, or have any idea what might be
causing it?  I'd rather not have to get a color monitor or new video board, when
I know this WAS working.  Please respond by e-mail, and I will post a summary
of responses in case anyone else is looking for an answer to the same question.
     Thanks in advance.

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     Robert Barrell - rbarrell at ls.com
     "Hodgepodge" - Sysop of Milo's Meadow - A Citadel/UX BBS
     215-323-0497 - 300/1200/2400 - 24hrs. - login as "bbs"
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