From 636d798da8311e9929ced20a7aa516e32d96b152 Mon Sep 17 00:00:00 2001
From: Leo C <erbl259-lmu@yahoo.de>
Date: Mon, 16 Mar 2020 14:20:06 +0100
Subject: [PATCH] Extended drive table for use with DRIVE.COM, a dynamic drive
 re-assignment utility.

---
 cbios/drvtbl.180 | 50 +++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/cbios/drvtbl.180 b/cbios/drvtbl.180
index 41d8cfb..abd8cd5 100644
--- a/cbios/drvtbl.180
+++ b/cbios/drvtbl.180
@@ -1,13 +1,57 @@
+;Extended CP/M 3 drive table for use with
+;DRIVE.COM, a CP/M 3 dynamic drive re-assignment utility.
+;
+;Originally written by Jim Lopushinsky, Edmonton Alberta
+
+
 	public @dtbl
 	extrn sd0,sd1,sd2,sd3
         extrn sd4,sd5,sd6,sd7
 	extrn cf0,cf1,cf2,cf3
 
-        cseg
+	cseg		;table is in common memory
 
 @dtbl	dw sd0,sd1,sd2,sd3	; drives A-D
         dw sd4,sd5,sd6,sd7      ; drives E-H
 	dw cf0,cf1,cf2,cf3	; drives I-L
-	dw 0,0,0,0		; drives M-P
+	dw 0,0,0,0		; drives M-P - not defined
+
+;Following is a table of existing drives.  This table can be used
+;to dynamically assign CP/M drives (A:, etc) to different physical
+;units.  Use BIOS function 22 (return address of drive table), and
+;add 32 to point to this table:
+
+	dw	sd0		;address of DPH for drive 0
+	db	'DSK0  '	;6 char unit name
+	dw	sd1
+	db	'DSK1  '
+	dw	sd2
+	db	'DSK2  '
+	dw	sd3
+	db	'DSK3  '
+	dw	sd4
+	db	'DSK4  '
+	dw	sd5
+	db	'DSK5  '
+	dw	sd6
+	db	'DSK6  '
+	dw	sd7
+	db	'DSK7  '
+	dw	cf0
+	db	'SIDE0 '
+	dw	cf1
+	db	'SIDE1 '
+	dw	cf2
+	db	'SIDE2 '
+	dw	cf3
+	db	'SIDE3 '
+	dw	0
+	db	'      '
+	dw	0
+	db	'      '
+	dw	0
+	db	'      '
+	dw	0
+	db	'      '
 
-        end
+	end
-- 
2.39.2