Xref: utzoo comp.unix.i386:1391 comp.unix.xenix:8700 comp.sources.wanted:9544
Path: utzoo!attcan!uunet!cs.utexas.edu!rice!uw-beaver!uw-entropy!thebes!campbell
From: campbell@Thalatta.COM (Bill Campbell)
Newsgroups: comp.unix.i386,comp.unix.xenix,comp.sources.wanted
Subject: Re: Fast parallel driver for Unix/Xenix AT?
Message-ID: <2316@thebes.Thalatta.COM>
Date: 24 Nov 89 21:59:23 GMT
References: <256ADBB5.19093@ateng.com>
Reply-To: campbell@Thalatta.COM (Bill Campbell)
Organization: Thalatta Corporation, Bellevue WA
Lines: 25

In article <256ADBB5.19093@ateng.com> chip@ateng.com (Chip Salzenberg) writes:
>SCO Xenix, like all AT Unixen, is shipped with a driver for IBM parallel
>ports.  Unfortunately, at least with SCO Xenix, the parallel driver uses the
>internal kernel data structures (clists) intended for use with serial lines.
>The use of clists lowers the speed of parallel to something far slower than
>the hardware could support otherwise.

There are problems with slow printing from Xenix with Tandy
printers in particular.  Most of these problems can be solved by
using the Tandy printer cables (they have some non-standard
crossovers).  There is also a patch to Xenix available from Tandy
to help speed up the printer.

Without the Tandy cables on Tandy printers the drivers shift into
a polling mode and the resulting print seems to have about a
half-second timeout between lines.

Another thing that will eliminate the problem is to use an
intermediate smart printer switch such as the $99.95 intelligent
switch from Tandy.
-- 
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