Atari 400 Basic Reference Manual

Pixel:
Precedence:
Program:
Prompt:
RAM:
Random Number
Generator:
Reserved Word:
ROM:
Save:
Screen:
Serial:
Software:
Special Character:
Statement:
String:
Subroutine:
Variable:
Window:
G-4 Appendix
Picture Element. One point on the screen display. Size depends on
graphics mode being used.
Rules
that determine the priority in which operations are conducted,
especially with regard to the arithmetical/logical operators.
A sequence of instructions that describes a process. A program must
be in the language that the particular computer can understand.
A symbol that appears on the monitor screen that indicates the com-
puter is ready to accept keyboard input. In Atari BASIC, this takes the
form of the word "READY". A "?" is also used to prompt a user to
enter (input) information or take other appropriate action.
Random Access Memory. The main memory in most computers.
RAM is used to store both programs and data.
May be hardware (as is Atari's) or a program that provides a num-
ber whose value is difficult to predict. Used primarily for decision-
making in game programs, etc.
See
Keyword.
Read Only Memory. In this type of solid-state electronic memory, in-
formation is stored by the manufacturer and it cannot be changed by
the user. Programs such as the BASIC interpreter and other car-
tridges used with the Atari systems use ROM.
To copy a program or data into some location other than RAM (for ex-
ample, diskette or tape).
The TV screen. In Atari BASIC, a particular I/O device codes "S:"
The opposite of parallel. Things happening only one at a time in se-
quence. Example: A serial interface.
As opposed to Hardware. Refers to programs and data.
A character that can be displayed by a computer but is neither a let-
ter nor a numeral. The Atari graphics symbols are special characters.
So are punctuation marks, etc.
An instruction to the computer. See also Command. While all com-
mands may be considered statements, all statements are certainly not
commands. A statement contains a line number (deferred mode), a
keyword, the value to be operated on, and the l;lilllh!ll command.
A sequence of letters, numerals, and other characters. May be stored
in a string variable. The string variable's name must end with a$.
A part of a program that can be executed by a special statement
(GOSUB) in BASIC: This effectively gives a single statement the power
of a whole program. The subroutine is a very powerful construct.
A variable may be thought of as a box in which a value may be
stored. Such values are typically numbers and strings.
A portion of the TV display devoted to a specific purpose such as for
graphics or text.

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)