SPACEWAR!

The argument

Spacewar! is where code first becomes play. Written across 1961-62 by Steve Russell and a circle of MIT hackers for the DEC PDP-1, in roughly two thousand words of Macro assembly it gave the computer a starfield, two ships, gravity, and a panic button. This project reads that program as a cultural text, in the tradition of Critical Code Studies: at once literature, mechanism, spatial form, and a repository of the social formation that produced it.

The object

No single Spacewar! source code: a family of versions. The early MIT releases (1, 2B, 3.1), the forked 4.x generation of 1963, later reconstructions such as the CHM 4.1f, and the many ports and clones of its long journey. The Versions page and the Timeline lay out the whole variorum.

• spacewar.mac: original Macro source (~2,057 lines)
• spacewar.lst: assembler listing, octal addresses + machine words
• originsources.zip: dated provenance snapshot
• spacewar.js: the PDP-1 emulator (play it)

/ spacewar 2b - 2 apr 1962 - pdp-1 macro assembly
/ one of many surviving versions (reconstructed by Norbert Landsteiner)

  define index A,B,C
    idx A
    sas B
    jmp C
  term

  define count A,B
    isp A
    jmp B
  term

The machine

1962 · 18-bit words · 4096 words of core · Type 30 CRT at 1024 x 1024 points, P7 phosphor · PDP-1 ~$120,000. The Type 30 was a point-plotting vector display derived from radar. This page is rendered in its spirit.

The reading

1. The machine that owns itself.
2. A language for ships (the Macro assembler's macros and outline compiler).
3. The Expensive Planetarium (Samson's real sky; Edwards's gravity).
4. Hyperspace, or the random jump.
5. The demo and the gift.
6. The founding myth and what it means for Spacewar!

Contacts

A collaboration bringing together critical code studies scholars and others.

• Prof. David M. Berry, Sussex (d.m.berry@sussex.ac.uk)
• Prof. Mark C. Marino, USC (mcmarino@usc.edu)