Sinclair ZX81 User Manual

Array of characters:
The part string at E_LINE contains the line being typed (as a command, a program line, or
INPUT
data)
& also some work space.
The calculator is the part of the BASIC system that deals with arithmetic, & the numbers on which it is
operating are held mostly in the calculator stack.
The spare part contains the space so far unused.
The machine stack is the stack used by the Z80 chip to hold return addresses & so on.
The
GOSUB
stack was mentioned in chapter 14.
The space for
USR
routines has to be set aside by you, using
NEW
as described in the last chapter.

Sinclair ZX81 Specifications

General

Processor	Zilog Z80A
Processor Speed	3.25 MHz
ROM	8 KB
Input	Membrane keyboard
Storage	Cassette tape
Power Supply	9V DC
Dimensions	167 mm x 40 mm x 175 mm
Release Year	1981
Manufacturer	Sinclair Research
Weight	350 g
Operating System	Sinclair BASIC
RAM	1 KB
Ports	TV out, expansion port
Display	Television (RF modulator output)