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From: catone@dsl.cis.upenn.edu.UUCP
Newsgroups: comp.sys.ibm.pc,comp.graphics
Subject: Re: How do I determine how much EGA memory is installed?
Message-ID: <988@super.upenn.edu.upenn.edu>
Date: Tue, 31-Mar-87 19:22:02 EST
Article-I.D.: super.988
Posted: Tue Mar 31 19:22:02 1987
Date-Received: Thu, 2-Apr-87 02:24:31 EST
References: <548@thumper.UUCP>
Sender: root@super.upenn.edu.upenn.edu
Reply-To: catone@dsl.cis.upenn.edu.UUCP (Tony Catone)
Organization: University of Pennsylvania
Lines: 26
Keywords: EGA, BIOS
Xref: utgpu comp.sys.ibm.pc:2651 comp.graphics:425

In article <548@thumper.UUCP> tr@thumper.UUCP writes:
>
>I know it's possible to determine how much memory is installed on an
>EGA board so that an application does not die from a false assumption
>of the amount of EGA memory present.  I know this because some
>applications print a message like "You need 256K to run this program."
>Does someone have a program written in C or Assembler that does this
>test?  I would like to see an example.
>-- 
>Tom Reingold
>Internet: tr@bellcore.com
>Uucp: ..!allegra!ulysses!faline!flash!tr

Service request 12 hex of BIOS video interrupt 10 hex returns EGA
information.  Upon return: bh signals color mode (0) or mono mode (1)
in effect; bl contains the memory on the EGA in its two least
significant bits (0 0 = 64K, 0 1 = 128K, 1 0 = 192K, 1 1 = 256K); ch
contains the feature bits; cl contains the switch setting.

The above is from the Proceedings of the IBM Personal Computer Seminar
on the EGA, which also contains sample code, though with the above
information you shouldn't need it.

					- Tony
					  catone@dsl.cis.upenn.edu
					  catone@wharton.upenn.edu