Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!mcvax!ukc!reading!cf-cm!sme
From: sme@computing-maths.cardiff.ac.uk (Simon Elliott)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: nnansi problems
Summary: peculiar behaviour with direct video writes
Keywords: nnansi, bugs
Message-ID: <812@cf-cm.UUCP>
Date: 16 Jun 89 10:11:22 GMT
References: <311@ohs.UUCP>
Organization: University of Wales College of Cardiff, Cardiff, WALES, UK.
Lines: 19


We run Novell Netware here, and some of the net management utilities have
a (very pretty) menu interface that appears to write direct to video ram.
These very quickly pointed out a problem with NNANSI, and (reluctantly) i've
reverted to NANSI -- I do like the speed of the new version.

Because the new NNANSI.SYS performs a hardware scroll by changing a register
strange things happen with programs that do direct video writes as the
screen memory is no longer where the program thinks it is.

It's not _really_ a bug in NNANSI -- programs writing to video ram should
check the base address register, but I wonder how many do?

-- 
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