Joyport

The Sirius Joyport was a game controller adapter for the Apple II computer designed by Keithen Hayenga and Steve Woita (who were employed by Apple at the time) and then licensed for manufacture and distribution in 1981 by Sirius Software. The device was meant to address a limitation in the built-in game control offered by the Apple II, by allowing either four Apple-compatible paddles or two Atari-style joysticks (but not both types at once) to be read by the computer simultaneously. The built-in game port on the Apple II, II+, IIe, and IIgs supports 4 analog paddles (or 2 analog sticks), but only 3 buttons.

With the Joyport, a game could support twice as many players as a standard Apple game port, but game designers had to specifically modify their code to take input from the Atari side of the Joyport. Many of them did so, and this modification is what is often seen listed in Apple II game configuration screens as the "Atari Joyport" option.

The recommended Atari joysticks were switch-driven (i.e. digital), instead of the smoother-action analog sticks that were already becoming available on the Apple II. Since the Apple II hardware made no distinction between two paddles or a single analog joystick plugged into the same jack, it would have also been possible to connect and read two fully analog joysticks with the Joyport via the paddle jacks, but few (if any) two-joystick games supported this, and Sirius did not suggest it. Why not is unclear, but there may have also been a noticeable speed advantage when driving two digital rather than analog joysticks on the limited hardware of the time.

The Joyport was a white plastic brick about the size of a paperback novel that connected to the standard (internal) Apple II gameport and broke it out into two Atari joystick ports and two Apple ports. A switch in the centre controlled whether to activate the paddles or the joysticks. Another switch could disable either the left- or right-side jacks (or neither).

Bundled in the package was the game Computer Foosball, which was written specifically by Hayenga to handle up to four players at once (through the Joyport) on the Apple II. Also included were BASIC and Pascal source code listings of sample programs making use of the Joyport, indicating the hobbyist influence in the market at the time it was released.

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