Tandy 1000 Programmer's Reference Guide

ChaDter 1 I System Calls
The following are error codes for Interrupt 24H:
Error Code Description
0
1 Unknown unit
2 Drive not ready
3 Unknown command
4 Data Error
5 Bad request structure length
6 Seek error
7 Unknown media type
8 Sector not found
9 Printer out of paper
A Write fault
B Read fault
C General failure
Attempt to write on write-protected disk
The user stack will be
in effect and, from top to bottom,
will contain the following:
IP MS-DOS registers from
cs issuing INT 24H
FLAGS
AX
BX INT 21H request
cx
DX
SI
DI
BP
DS
ES
IP From the original INT 21H
cs from the user to MS-DOS
FLAGS
User registers at time of original
If an IRET is executed, the registers are set to cause
MS-DOS to respond according
to the contents of AL as
follows:
AL
=0 ignore the error
=1 retry the operation
=2
terminate the program via 23H
18

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