Atari 2600 to Analog Circuit

Question

I've seen one of Ben's Portable Atari Consoles with an analog joystick. I've searched for info but to no avail. Can anyone point me in the right direction on circuitry for an analog joystick (PS2 controller) to be used with the Atari 2600. Currently the Atari controller has just 5 inputs ie up, down, left, right, fire plus a common ground.

Any info would be greatly appreciated!

benheck · Answer

It's been so long I can't remember exactly how I did that.

Probably put ground on the center of the pot, and up/down (or left/right) on the outer terminals.

This way, moving the stick would cause the joystick direction line to get closer to ground, eventually triggering. It would likely "go low" well before actually hitting 0 volts.

-Ben