Mapping the Atari

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Mapping the Atari
Mapping the Atari.jpg
First edition
AuthorIan Chadwick
CountryUnited States
Subject Atari 8-bit family
Publisher COMPUTE! Publications
Publication date
1983, 1985
ISBN 0-87455-004-1
OCLC 13271042
005.265 19
LC Class QA76.8.A82 C424 1985

Mapping the Atari, written by Ian Chadwick and published by COMPUTE! Publications in 1983, is a location-by-location explanation of the memory layout of the Atari 8-bit family of home computers. The introduction is by Optimized Systems Software co-founder Bill Wilkinson.


The book covers the 64K address space of the system's 6502 processor from low to high, including addresses used by the operating system or mapped to hardware registers, as well as how to use them. For example, location 756 (2F4) CHBAS contains the starting memory address that tells ANTIC where to find the character set. The author explains how to use this feature to build custom character sets.

An updated version covering changes to the operating system and newer machines like the 130XE followed in 1985. Antic magazine serialized the book in 1989 and 1990. [1] [2] [3] [4]


The Addison-Wesley Book of Atari Software 1984 recommended Mapping the Atari, calling it "the most valuable reference book for machine language programmers". [5]

Antic stated when serializing the book: [1]

Ian Chadwick's "Mapping The Atari" has been one of the core references for Atari 8-bit programmers since the first edition was published in 1983... But it is much more than that. It is a virtual encyclopedia of indispensible[ sic?] information about the inner workings of the Atari.

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  1. 1 2 Chadwick, Ian (August 1989). "Mapping the Atari". Antic. pp. 22–27.
  2. Chadwick, Ian (September 1989). "Mapping the Atari, Part 2". Antic. pp. 9–14.
  3. Chadwick, Ian (October 1989). "Mapping the Atari, Part 3". Antic. pp. 13–16.
  4. Chadwick, Ian (December 1989 – January 1990). "Mapping the Atari, Part 4". Antic. pp. 17–20.
  5. Stanton, Jeffrey; Wells, Robert P.; Rochowansky, Sandra; Mellid, Michael, eds. (1984). The Addison-Wesley Book of Atari Software. Addison-Wesley. p. 418. ISBN   0-201-16454-X.