An arcade machine with no one playing it does not sit still. It runs through its title, a scrap of story, the high-score table and a game played by the machine itself, over and over, until somebody drops in a coin. In December 1980 COMPUTE! explained the name to home-computer owners: “it’s called ‘attract mode’ because in arcade games the machine goes into its special sales pitch to attract customers. Check out Space Invaders between games to see what I mean.” The pitch mattered. A British partwork on home computing put it plainly in the mid-1980s: “The success of a game designed for the arcade often depends on the persuasiveness of its ‘attract’ mode”, and a game that failed to persuade “will soon be removed by the arcade owner in favour of a more profitable” one.
Fast facts
- What it is: the loop an arcade game runs while no one is playing: title, story, scores and a demonstration.
- Why: to attract players to an idle machine, and to show them how the game works before they pay.
- At home: usually called the demo mode; a self-running demo was being advertised for Apple II games by 1980.
- How: most demonstrations run the real game, fed with stored controller input instead of a player’s.
- A second meaning: on Atari’s home computers, “attract mode” was the colour-cycling the system used to protect an unattended television.
The sales pitch
A coin-op has to sell itself to someone walking past. The attract mode was where it told its story, showed off its graphics and, above all, showed itself being played. Video Games Player described it in 1983 as the time “when the game is playing itself”. Story mattered too. Video Games reported that Star Wars’ attract mode “takes its cue from the movie”, with the official logo and a short paragraph telling the story, and that Centuri’s Aztarac told its plot there (“4031 A.D. A thousand years of interstellar peace has come to an end”). For the laserdisc games of 1983 and 1984 the attract mode was the showcase; the magazine complained of Bega’s Battle that its “wonderfully exciting animated scenes are primarily limited to the attract mode”.
Some players were won over in exactly the way the designers hoped. Jeff Minter remembered walking past a sit-down cabinet in London’s Piccadilly Arcade in 1980 as it spelled out “Exidy EXCITEMENT Brings You… STAR FIRE”, “shortly followed by the attract mode, which revealed a first-person space shooting game heavily based on Star Wars”. Fresh from seeing The Empire Strikes Back, he climbed straight into the cockpit.
The pitch could shape the game itself. Bob Pape, who converted R-Type to the Spectrum, noticed that the arcade game’s first level was its longest and most varied, and decided the reason “was purely commercial”: “in the arcade this is the attract mode, the level that would be played the most by gamers so it made sense to make it interesting”. Others thought the effort went to the wrong place. “People spend so much time on the attract mode, and the title screen, and FMV,” Eugene Jarvis told Edge in 1996, when they “should spend time on the game itself.”
Looking back in 2011, Seamus Blackley, one of the creators of the Xbox, described the arcade business he grew up with as one in which “a game had to succeed or fail for a completely casual audience, with no marketing, based on its attract mode or the first 30 seconds of play.”
Watching the demo
Players learned from it. Videogaming Illustrated advised newcomers to Sega’s driving game Turbo to “watch the attract mode to familiarize yourself with the course”. Video Games suggested that anyone who wanted to know how hard Rosen’s Brigade could get should “watch the game play itself during its attract mode”, in which, at the highest level, the convict dropped 13 bombs a second. It also recommended studying the attract mode of a home Frogger, “because it displays invaluable game playing tips”.
The demonstration also caught people out. A 1984 quiz in the British magazine TV Gamer gave one mark of an inexperienced Defender player as: “They forget to put a coin in the machine and try to play the attract mode.” Some games could be bent into letting people do just that. JoyStik published codes for Atari’s Tempest in 1983 that worked by finishing a game with a score ending in particular digits; one of them, ending in 05, “allows playing during attract mode”.
Bootleggers used the attract mode for the opposite purpose. To avoid legal trouble, Video Games Player warned in 1983, a pirate “may make some minute changes in the attract mode, the game title or the game characters” of the game he copied, and it told readers to watch a machine’s attract mode to see whose name was on it.
How the demonstration works
Most demonstrations run the real game, with the program pretending to be the player. The disassembly of Nintendo’s Super Mario Bros. published by the programmer known as doppelganger shows how small this can be. A routine called DemoEngine reads from two tables: DemoActionData, about twenty sets of joypad buttons, and DemoTimingData, how many frames to hold each one. Each frame it hands the current buttons to the game, which then runs exactly as it would for a player. When the timings run out, the demo ends and the title screen returns.
Konami’s NES Contra does the same for two players at once. The annotated disassembly of the American version shows a table for each player on each of its three demonstration levels, made of pairs of bytes: a controller value and the number of frames to hold it, ending with $FF. The program adds the shooting itself, holding the fire button down for the machine gun and laser and tapping it every eighth frame for the other weapons. Pressing Start or Select ends the demonstration.
Because the game logic is real, a demonstration like this only works if the game behaves the same way every time it is given the same input. A different approach lets the computer’s own opponents play both sides. The Raspberry Pi Press book Code the Classics uses it for Boing!, its Python version of Pong, whose menu screen shows “two computer-controlled players playing against each other in the background”.
Demo modes at home
Home games borrowed the idea at once. In 1980 an advertisement in Creative Computing sold Super Invasion for the Apple II with a “self-running ‘attract mode’ of operation for easy learning and demonstrating of the game”. In 1983 Computer Gaming World called the attract mode of Wayout the best it had seen: “The program actually solves the INTRO maze, while demonstrating all game features.”
Richard Mansfield explained the idea to beginners in Machine Language for Beginners (1983), and again in COMPUTE!’s Gazette in 1986. Machine-language games, he wrote, often never end at all: “Arcade games which cost a quarter will ask for another quarter, but they don’t end. They go into ‘attract mode.’ The game graphics are left running on screen to interest new customers.”
British reviewers treated a good demo as part of a game’s presentation. ZZAP! 64 weighed the attract mode alongside the options when it rated presentation: “Really pretty attract mode but no options” for Rupert and the Ice Palace (1985), “Simple attract mode and one or two player option” for Crazy Comets. In its first issue it described the demo in Caverns of Sillahc, which showed “the whole playing area and the hazards within it”, and called it “handy for planning your way around and spotting where all the robots are”. In 1988 the magazine praised the attract mode of Konami’s arcade Vulcan Venture, “showing pictures of the two previous games” in the series.
On small machines a demo cost memory. Pape’s Spectrum R-Type was meant to have one. In his own account of the conversion, he wrote an attract mode, which “got dropped due to lack of space”.
Atari’s other attract mode
On Atari’s 400 and 800 home computers, “attract mode” meant something else. Atari’s own programming guide, De Re Atari, described it as a feature of the operating system: “After nine minutes without a keypress, the colors on the screen begin to cycle through random hues at lowered luminances. This ensures that a computer left unattended for several hours does not burn an image into the television screen.” The operating system changed the colours every four seconds by mixing a random value into the colour registers and dimming them.
It was one more thing for programmers to look after. A program that set colours directly, for example in a display list interrupt partway down the screen, defeated the system’s attract mode, and De Re Atari showed the two extra instructions that would put it back. A game controlled only by joysticks had the opposite problem. The timer was reset by key presses, so, as one guide to the Atari’s memory warned, a program using joysticks but not the keyboard had to reset it “every few minutes” itself, or the screen would start changing colour in the middle of play.
Later
By the mid-1990s an attract mode could be a technical showcase in its own right. Edge reported that Sega Rally’s featured “dozens of jawdropping sequences”, and that Virtua Fighter’s attract mode and replays gave players “the chance to admire the superbly designed and animated characters”. For a while the magazine ran a regular page called “Attract Mode”, celebrating game introductions. Home conversions sometimes copied the arcade’s loop as a feature: the 3DO Super Street Fighter II Turbo kept “the original arcade machine’s Attract mode, showing Ryu limbering up and launching a fireball”.
Sources
- COMPUTE! issue 7, December 1980, p. 58: the Atari’s colour cycling and the meaning of “attract mode”.
- The Home Computer Advanced Course part 33 (Orbis), p. 22: an arcade game’s success and its attract mode.
- Video Games Player vol. 2 no. 2, November 1983, p. 31: the game “playing itself”; pirate copies.
- Video Games vol. 2 no. 1, October 1983, p. 55: Star Wars. Vol. 2 no. 4, January 1984, p. 55: Aztarac. Vol. 2 no. 5, February 1984, p. 61: Rosen’s Brigade. Vol. 2 no. 6, March 1984, pp. 41 and 80: Bega’s Battle; Frogger.
- Jeff Minter and Patrick Minter, A History of Llamasoft (Llamasoft, 2009), pp. 47–48: Star Fire in the Piccadilly Arcade.
- Bob Pape, It’s Behind You: The Making of a Computer Game (2013), pp. 42 and 71: the first level of R-Type; the Spectrum attract mode dropped.
- Edge issue 37, October 1996, p. 24: interview with Eugene Jarvis.
- Edge issue 231, September 2011, p. 94: interview with Seamus Blackley.
- Videogaming Illustrated, October 1982, p. 44: Turbo.
- TV Gamer, July 1984, p. 38: quiz.
- JoyStik vol. 2 no. 1, September 1983, p. 62, and vol. 2 no. 3, December 1983, p. 6: Tempest codes.
- doppelganger, SMBDIS.ASM: a comprehensive Super Mario Bros. disassembly (web):
DemoEngine,DemoActionData,DemoTimingData. https://gist.github.com/1wErt3r/4048722 - vermiceli, Contra (US) disassembly, version 1.3,
bank5.asm(web): the demonstration input tables. https://github.com/vermiceli/nes-contra-us - Eben Upton and others, Code the Classics, volume 1 (Raspberry Pi Press, 2019), p. 37: Boing! and its attract mode.
- Creative Computing, April 1980, p. 25: Super Invasion advertisement.
- Computer Gaming World issue 10, May 1983, p. 31: Wayout.
- Richard Mansfield, Machine Language for Beginners (COMPUTE! Books, 1983), p. 124; “A Gateway To Machine Language”, COMPUTE!’s Gazette issue 40, October 1986.
- ZZAP! 64 issue 1, May 1985, p. 55: Caverns of Sillahc. Issue 8, December 1985, pp. 33–35: Rupert and the Ice Palace, Crazy Comets. Issue 39, July 1988: Vulcan Venture.
- Atari, De Re Atari (1982), “Display list interrupts”: attract mode, COLRSH and DRKMSK.
- Lon Poole and others, Your Atari Computer (Osborne/McGraw-Hill, 1982), memory map: location 77, ATRACT. Craig Patchett and Robin Sherer, Master Memory Map for the Atari (Reston, 1984), location 77: resetting ATRACT in joystick programs.
- Edge issue 17, February 1995, pp. 59 and 70: Virtua Fighter on the Saturn; Super Street Fighter II Turbo on the 3DO. Issue 18, March 1995, p. 35: Sega Rally. Issue 8, May 1994, p. 8: the “Attract Mode” page.