Path: utzoo!attcan!uunet!ispi!jbayer
From: jbayer@ispi.UUCP (id for use with uunet/usenet)
Newsgroups: comp.unix.xenix
Subject: Re: COM3 with Xenix 2.2.3
Summary: com3 and com4 are wrong except on a sperry
Message-ID: <225@ispi.UUCP>
Date: 20 Oct 88 14:00:09 GMT
References: <1113@lakesys.UUCP> <3700004@eecs.nwu.edu> <10119@cup.portal.com>
Organization: Intelligent Software Products, Inc.
Lines: 17

In article <10119@cup.portal.com>, MichaelNC@cup.portal.com (Michael Kent Brady) writes:
> Or try  "mkdev serial"  
> 
> Mine allows COM1 thru COM4

I have said it before, I will say it again.  RTFM!!!  Com3 and com4 are only 
for use on the Sperry IT 286 boxes (I don't know about the 386).  Sperry,
now known as Unisys, has some special logic on the board to handle com3 and
com4.  It is not available and will NOT work on any other computer.  Also,
the multiport cards which are supported each occupy either com1 or com2.  The
drivers take care of the different serial lines associated with each card.  This
is all very well documented in the Release Notes which accompany every copy of
the OS.  They should always be your first reference when working with
hardware.

Jonathan Bayer
Intelligent Software Products, Inc.