Xref: utzoo comp.sys.tandy:2891 comp.sys.ibm.pc.hardware:4487
Newsgroups: comp.sys.tandy,comp.sys.ibm.pc.hardware
Path: utzoo!censor!meadow!py
From: py@meadow.uucp (Peter Yeung)
Subject: Re: Tandy 4000 vs. Wang VGA incompatibility
Message-ID: <1991Jan14.061911.6740@meadow.uucp>
Reply-To: py@meadow.UUCP (Peter Yeung)
Organization: Amdahl Canada Ltd., Software Development Center
References: <1991Jan11.190207.1992@vax5.cit.cornell.edu>
Distribution: comp
Date: Mon, 14 Jan 91 06:19:11 GMT

In article <1991Jan11.190207.1992@vax5.cit.cornell.edu> jeh@vax5.cit.cornell.edu writes:
>I've got a Tandy 4000 at home, with a rev. C1 motherboard and
> ... system description deleted...
>further in the start-up sequence.  I eliminated all cards except
>32-bit memory and Tandy's serial/parallel card, to no effect.
>

I have never used a Tandy box, the following is mainly my experience with other
systems:

The major questions to be asked are: 

(1) is the VGA card an 8 bit or 16 bit card?

(2) is there any addressable card within the video ROM BOIS segment,
    typically C000:0000 (e.g. SCCI controller with its own BIOS or RAM card 
    covering the same segment)?

If your card is an 8 bit card and a 16 bit peripheral card (or vis-versa)
are sitting in the same segement, it will be in a conflict and will not work.

If both peripheral cards are same bus size (e.g. both are 16 bit), make sure
their addresses do not overlap.


I would strip down the system to a care minimum (i.e. include pulling out
additional RAM cards) and add a card at a time in order to isolate the
problem. If your system cannot boot with the base memory/floppy drive/VGA card,
the conflict is definitely between the VGA card and the motherboard and may
not be easily resolved.

Hope this will help!

-- 
Peter Yeung     Amdahl Canada Ltd., Software Development Center
                2000 Argentia Road, Plaza 2, Suite 300
                Mississauga, Ont.   L5N 1V8
                Phone: (416) 542-6300    Fax: (416) 858-2233