Atari 800 User Manual

Introduction to Atari BASIC 41
is executed, the program is re-executed. As previously
discussed, in the immediate mode, each program line is
executed when the Return key is pressed.
Program Lines & Display Lines
A display line can be defined as one row on the video display. A
program line is regarded by the BASIC interpreter as one line,
regardless of the number of display lin es it occupies on the
screen. The end of a program line is signaled when the Return
key is pressed.
Program
lines generally are limited to 114 characters. If you are
entering a lengthy program line, the Atari will beep when the
107th character has been input. This is intended as a warning to
the operator that he is approaching the limit of the program line.
Multiple Statement Program Lines
A statement can be defined as an instruction to the computer.
The terms statement and command are often used interchange-
ably. Most programs consist of a large number of statements. The
following are examp l es of statements.
PRINT "Tim Gregory"
070 DIM A(lS)
100 C = 2*B
Every
statement in Atari BASIC must contai n at least one key or
reserved word. A keyword identifies the ca lculat ion , decision,
input, or output function to be performed. The keywords are
described individually in Chapter 5 and are listed in alphabetica l
order in Appendix B.
In addition to keywords , numeric constants, string constants,
variabl es , and special symbols may appear in a BASIC statement.
These are known as the statement parameters.
Atari BASIC allows the user to place more than one statement on
a s ingl e program lin e. Multiple statements must be separated
with a colon (:). The following is an example of a multiple

Atari 800 Specifications

General

Processor	MOS Technology 6502
Processor Speed	1.79 MHz
ROM	10 KB
Graphics	ANTIC and GTIA chips
Release Year	1979
Display Resolution	up to 320 x 192
Colors	128 colors
Sound	4 channels
Storage	Cartridge, cassette, floppy disk
Ports	Cartridge, serial, monitor
Operating System	Atari OS