Tandy 1000 Programmer's Reference Guide

Chapter 1 I System Calls
SelectDisk
Select Disk Function Call OEH
Selects the specified drive as the default drive.
Entry Conditions:
AH = 0EH
DL = new default drive number ('0 = A, 1 = B, etc.)
E xi t Conditions :
AL = number of logical drives
Macro Definition:
select-disk macro disk
mav dl,dlsk[-641
mov ah,0EH
int
21 H
endm
Example:
The following program selects the drive not currently se-
lected in
a 2-drive system.
func-0EH: current-disk ;see Function 19H
cmp al,00H ;drive A selected?
le select-
b ;yes, select B
select-disk "R" ;THIS FUNCTION
Imp continue
select-
b: select-disk "E" ;THIS FUNCTION
continue:
48

Tandy 1000 Specifications

General

Processor	Intel 8088
Processor Speed	4.77 MHz
RAM	128 KB (expandable to 640 KB)
Operating System	MS-DOS 2.11
Manufacturer	Tandy Corporation
Release Year	1984
Storage	Single or double 5.25" floppy disk drive (360 KB), optional hard drive
Sound	Tandy 3-voice sound
Ports	Parallel, Serial
Graphics	CGA (Color Graphics Adapter)
Graphics Modes	320x200, 640x200