Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!apple!sun-barr!newstop!sun!imagen!qmsseq!pipkins
From: pipkins@qmsseq.imagen.com (Jeff Pipkins)
Newsgroups: comp.sys.ibm.pc
Subject: Re: VGA versus Ethernet versus IBM PC/AT
Keywords: Ethernet, AT-3, WD8003EBT, etc.
Message-ID: <50@qmsseq.imagen.com>
Date: 30 Nov 89 16:16:37 GMT
References: <1159@cernvax.UUCP>
Reply-To: pipkins@qmsseq.UUCP (Jeff Pipkins)
Organization: QMS Inc., Mobile, Alabama
Lines: 30

When installing a Western Digital WD8003 Ethernet board in a
system with a VGA and EMS, may I suggest locating the WD8003
at segment address CE00 (hex)?  The VGA card mapping ends at
C7FF but the WD8003 won't map at C800, and besides, there is
usually a ROM module that resides there.  EMS usually starts
at D000, so CE00 looks like a cozy little hole for the 8K
needed.

IRQ line allocation: XTs use IRQ 5 for the hard disk; IRQ 5 is
informally assigned to parallel port 378 (hex) on the AT.
Even if you have more than one LPT port on your AT (or 386),
chances are incredibly high that you're still not using IRQ 5.

IRQ 7 is for parallel port 3BC and is rarely used by anything
other than background despoolers.

IRQ 4 is for serial port 3F8; IRQ 3 is for serial port 2F8.
Either of these unused is fair game for your WD board.

Check for possible conflicts with a bus mouse card, if you
have one.

Good Luck!

/*========================================================================*\
   Jeff Pipkins: pipkins@imagen.com  My views are not necessarily shared 
   by my employer or the IRS.  That explains a lot about my paycheck.

   "Why is it that unpitted dates have pits and pitted dates do not?"
\*========================================================================*/