Atari BASIC Programming Language [Model CXL4002]

The Atari 800 Software by Atari, Inc.



Emulated in MAME ! [Computer] Atari 800 Software

Atari BASIC Programming Language © 1979 Atari, Inc.


Model CXL4002


The original cart releases were labeled BASIC Computer Program, which was later changed to BASIC Computing Language. The last releases were labeled Atari BASIC Computing Language.


Three versions exist, A, B, and C.
A was used primarily in the 400/800 computers, B in the XLs, and C in the XEs.
Aside from being built-in in all the different machines, rev B and C carts were also made. To determine what version you have enter PRINT PEEK (43234). Rev A returns a value of 162, Rev B is 96, and Rev C is 234.

Rev A was a beta version from SMI (Shepardson Microsystems, Inc.), the company Atari contracted to write Atari BASIC. As a result of trying to fit the program onto an 8K cartridge, as well as working on a tight schedule, Atari BASIC was plagued by 2 problems that caused it to be one of the slowest-performing BASIC languages for any computer – a poor implementation of line number lookups in loops and jumps, and a poor implementation of multiply and divide. Unfortunately, Atari never corrected the problem in subsequent versions, even though SMI identified and fixed a number of bugs (some serious) that cropped up in the initial release.

Game's ROM.

Page last modified on June 20, 2016