Atari 5200 controller adapters

danjovicdanjovic wrote 11/25/2019 at 02:48 • 3 min read • Like

The Atari 5200 controllers are well known by its low reliability. Many alternatives to the original controllers have rose along the time  from when the sytem was being sold on stores up to present days when it is possible to find adapters being produced and sold by members of Atari Age community forums. The adapters found today can be either:

a) analog - based on digital potentiometers or

b) digital - based on switched resistors.

Both change resistance in a RC network that is used by the console to convert a time measurement into positional information.

There are other ways to do it, though:

  1. Applying a variable voltage on a fixed resistor. The charging time depends upon the RC constant for a given potential difference (voltage). That is pretty much how the trackball works.
  2. Detecting the moment the timing capacitor start to charge and hold the voltage low until the correct timing has passed. On the 5200 it is a tricky task, because the capacitors do not receive a pulse (of known time) to discharge. Instead they are held discharged until the CPU generates a pulse internally that releases the charge.

I have figured out the methods above after went through plenty of technical information such as datasheets, books and forum posts. In the meantime I have worked on the design of some alternative controller adapters:

Norris: Adapater for Wii Nunchuck controller.

Hunter: Adapter for Playstation Dualshock controller.

Stingray: Adapter for Wii Nunchuck Classic controller

Concept board for StingRay

Second controller (for dual stick games) is connected through P2 Jack. If necessary GND connection wire can be used for one of the triggers of the second controller.