The 128 introduced the ability to save to the +D Disciple disk system, but lost its joystick port.

The official reason for changing the joystick ports was to reduce RF interference.

Attached via a joystick port controlled at 15625 baud horizontal video timing.

Other uses for the joystick ports include light pens.

This version supported only two players as the additional joystick ports had been removed from the 8-bit machines some time earlier.

It also included two standard Atari-style joystick ports.

Also, the device is not compatible with games that uses any of the other accessories due to the lack of an additional joystick port.

The system also features four joystick ports, a cartridge connector, and an expansion port.

The interface itself would be attached to the computer's rear expansion port with a single joystick port on the front or top of the system.

It was used in Atari 800 family of computers (to provide four joystick ports to the machine).