Atari 800 User Manual

Atari BASIC Reference Guide 125
the subroutine at line 200 is executed. If X =3 , the subroutine at
line 300 is executed. If X = 4, the subroutine at line 400 is
executed. If X = 0 or X is greater than 4, the next line is executed.
GOlO
The GOTO statement causes the program to proceed at the
indicated line number.
CONFIGURA TlON
GOTO LN
EXAMPLE
10 X = X + 1
20 IF X /\ 2>50 THEN END
30 PRINT X;
40 GOTO 10
RUN
1234567
The previous
example demonstrates the use of GOTO . Line 10
increases the value of X by 1. Line 20 ends the program when X
squared is greater than 50 . When line 40 is executed, the
program returns to line 10 . This program repeats lines 10 through
40 until the program is ended or branched out of the loop. The
program ends when X = 8 because 8 squared is greater than 50.
GOTO is also used with an ON statement to branch a program to
one of several line s.
CONFIGURATION
ON EX GOTO LN [,LNj [,LNj ...
The expression after
the ON statement indicates which line
number the program proceeds to. This is called the control
expression. The control is evaluated and rounded off . If the
value is negative or greater than 255, an error occurs. If the value
of the control is 1, the program continues at the first line number

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