Tandy 1000 Programmer's Reference Guide

Chapter I / System Calls
Error Returns:
AX = 6
Invalid handle. The handle passed in BX is not cur-
rently open.
Invalid Function. The function passed in
AL was not
in the range 0-7.
Invalid data.
Access denied (for calls
AL = 4, 5, 6, 7).
AX = 1
AX = 13
AX = 5
Example:
loct I equ
mov
(or mav
mov
(or Ids
mov
mov
mov
Int
44H
bx, handle
bl, drive for call5 fiL = 4,s)
dx, data
dx, buffer and
dx,
count for calls (IL = 2,
al, function
ah, loctl
21 H
3, 4, 5)
119

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