Arcade controller

An arcade controller is a collective set of input devices designed primarily for use in an arcade cabinet. A typical control set consists of a joystick and a number of push-buttons. Less common setups include devices such as trackballs or steering wheels. These devices are generally produced under the assumption that they will be used in commercial settings, such as in video arcades, where they may be heavily or roughly used. Durability is one of the distinguishing characteristics of "authentic" arcade parts when compared with numerous, low-cost arcade imitations designed for private use in the home.

A typical joystick is a digital input device that registers movement according to the range of motion that it is designed to detect. Most modern joysticks have an 8-way configuration, allowing for movement in the cardinal directions and the diagonals. There also exist common "analog" sticks that in actuality are implemented as 49-way digital, with incremental degrees of movement in each direction. Many vintage arcade games use a 4-way or even 2-way stick rather than an 8-way stick, which can cause compatibility problems that may be mitigated by the use of an appropriate restrictor gate.

The two most common arcade joystick shapes are the ball top and bat top style. In North America the bat top is by far the most common with the ball top style being most common in Japan. The shape of the joystick is largely considered a matter of personal preference and comfort, as different types of grips are possible with each shape.

A restrictor gate limits the joystick's range of motion. The most common reason to use a gate in an actual arcade setting is the retrofitting of an older machine that is not compatible with a new 8-way stick. A classic example of this is Pac-Man. The game was originally designed for a 4-way stick, and is programmed to respond only when a new input occurs. If the user is holding the stick in the down position, then suddenly makes a motion to move to the right, what often happens is that the stick first moves into the down-right diagonal, which the game does not recognize as new input since down is still being held. However, right is also now considered held, and when the user completes the motion to move right, it is also not a new input, and Pac-Man will still be moving down.

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