About

This is a virtual DEC PDP-1 emulated in HTML5/JavaScript running the original code of "Spacewar!", the earliest known digital video game. If available, use gamepads or joysticks (currently Chrome and Firefox only, see instructions-memo below) for authentic gameplay — the game was originally played using custom control boxes. Spacewar! was conceived in 1961 by Martin Graetz, Stephen Russell, and Wayne Wiitanen. It was first realized on the PDP-1 in 1962 by Stephen Russell, Peter Samson, Dan Edwards, and Martin Graetz, together with Alan Kotok, Steve Piner, and Robert A Saunders. – Spacewar! is in the public domain, but this credit paragraph must accompany all distributed versions of the program. This implementation by Norbert Landsteiner, www.masswerk.at, 2012–2016. Based on emulation code by Barry Silverman, Brian Silverman, and Vadim Gerasimov. The emulation code was extended to support some additional instructions and auxilary hardware. Especially the shift/rotate instructions and the arithmetics were rewritten and now include an emulation of the automatic hardware multiply/divide option. Further, cycle counts were added for accurate timing and frame rates. Some importance was put in the recreation of the appearance of the original CRT display and the unique experience conveyed by it. Moreover, a splash-screen was added, and there are multiple versions of the original code ready to play. See below for details. For some other interactive programs running on this emulator, see www.masswerk.at/minskytron. The original PDP-1 emulation in HTML5/JavaScript running Spacewar! by Barry Silverman, Brian Silverman, and Vadim Gerasimov is to be found at: http://spacewar.oversigma.com/html5/.