Tandy 1000 Owner's Manual

Contents
Introduction .................................................................... i
1 Description of the PC Modem ............................. 3
DIP switches
................................................................... 4
Installation ..................................................................... 6
Communications protocol .................................................. 15
2 Operation .................................................................... 17
Registers
......................................................................... 20
Command codes
.............................................................. 17
Result codes
.................................................................... 22
Logons in MS-DOS operating systems
.................................. 23
Appendices
A Command reference
................................................. 27
Programming commands
................................................... 27
Registers
......................................................................... 32
Data line monitoring
......................................................... 36
B Troubleshooting ........................................................ 37
Analog loop self-test
......................................................... 37
C Specifications ........ 1 .................................................... 39 .
Performance ................................................................... 39
Physical/environmental
..................................................... 39
D Schematic diagram ................................................... 41
Index ................................................................................. 43

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