Atari 400 User Manual

54 User's H andbook to the Atari 400/ 800 Computers
number's sign, that usage is known as a unary operation. Unary
operators can be used to change the sign of a numeric constant
or variable as shown below:
100 LET A = -A
When unary operators are used in the manner shown above, the
unary operation is regarded as an a rithm etic operation .
The
term arithmetic expression is used to describe the us e of an
arithmetic operator with numeric constants and/ or variables.
The following are examples of ar ithm etic expressions.
x + Y + 70
100 / A + B
3000 * 10 + 1
Exponentiation is the process of raising a number to a specified
power. For example, in the following,
the numeric variable A would be eva lu ated as:
A*A*A*A*A
In BASIC, exponentiation is indi cated with the caret symbo l, 1\
Exponentiation can be us ed in an arithmetic expression as s hown
below:
8*3+71\2
The pre ced ing expression would eva luate to 73 .

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)