Atari 400 Basic Reference Manual

PREFACE
This manual assumes the user has read the Atari BASIC - A Self-Teaching
Guide or some other book on BASIC. This manual is not intended to "teach"
BASIC. It is a reference guide to the commands, statements, functions, and
special applications of Atari® BASIC.
The programs and partial programming examples used in this manual are
photostats oflistings printed on the Atari 820™ Printer. Some of the special sym-
bols in the Atari character set do not appear the same on the printer; e.g., the
clear screen symbol '~" appears as a " } ". The examples in the text were
chosen to illustrate a particular function- not necessarily "good" programming
techniques.
Each of the sections contains groups of commands, functions, or statements
dealing with a particular aspect of Atari BASIC. For instance, Section 9 contains
all the statements pertaining to Atari's unique graphics capabilities. The appen-
dices include quick references to terms, error messages, BASIC keywords,
memory locations, and the AT ASCII character set.
As there is no one specified application for the Atari Personal Computer System,
this manual is directed at general applications and the general user. Appendix H
contains programs that illustrate a few of the Atari system's capabilities.
Preface vii

Atari 400 Specifications

General

Manufacturer	Atari
Model	400
Type	Home Computer
Release Year	1979
CPU	MOS Technology 6502
CPU Speed	1.79 MHz
ROM	10 KB
Operating System	Atari OS
Keyboard	Membrane keyboard
RAM	8 KB (expandable to 48 KB)
Graphics	ANTIC and GTIA chips
Sound	4 channels
Display	RF output for connection to TV
Storage	Optional cassette tape drive or floppy disk drive
Ports	Cartridge
Display Resolution	320x192 (16 colors)