Atari 800 User Manual

92 User's Handbook to the Atari 400/ 800 Computers
ABS
The ABS function returns the absolute value of its argument.
ADR
Configuration
x = ABS(a)
Example
PRINT ABS(-81)
81
The ADR fu nction returns the memory add ress of the argument.
The
argument must be a string variable or a string constant.
In BASIC, a machine language program can be put in a string
variable. However , the operating system moves variables around
to efficiently use memory. As a result, to call a machine language
routine, the ADR function is used to locate the string.
Configuration
x = ADR(a$)
Example
x = ADR(B$)
AND
AND is used between two expressions, and returns the value 1 if
they are both true, and 0 if either one is false.
CONFIGURATION
EX AND EX

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