From: James Webb <james AT ee DOT adfa DOT oz DOT au>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Detecting connected disk drives
Date: Tue, 21 Jan 1997 17:26:44 +1100
Organization: Electrical Engineering, University College UNSW ADFA Australia
Lines: 29
Message-ID: <32E461A4.41C67EA6@ee.adfa.oz.au>
References: <VxLWbFAJI$0yEwhL AT talula DOT demon DOT co DOT uk>
NNTP-Posting-Host: 131.236.30.20
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Shawn Hargreaves wrote:
> . . . or detect whether disk B really exists, but I have no idea
> how to do either. . .

Shawn!

	I have no idea if this will be useful (as I have no idea whan an
Allegro is!), but if you want to stuff around with interrupts and
assembly (there is heaps of chat on this newsgroup about both), try:

Untried #1:
	Issue a BIOS interrupt INT 11H, and test bits 6 & 7 in the AX upon
return.  These bits indicate the number of attatched diskette drives.
(00 = 1, 01 = 2, 10 = 3, and 11 = 4).

OR... tried #2:	(Sorry about the Intel syntax!)
	MOV    AH,15H	
	MOV    DL,0	;To test for drive B, use MOV   DL,1	
	INT    13H
	CMP    AH,0
	JZ     DRIVE_A_NOT_PRESENT	; ie AH = 0 if drive not present

Hope this is useful!

Chow,
	James
------------------------------------------------------------------------
"Life would be so much easier if we could just look at the source code."
------------------------------------------------------------------------