Atari 5200 Controller to 9 pin port adapter?

[YSG2020]

Does anybody know if there is a 5200 controller to 9 pin inline cable adapter to enable plugging a 5200 controller into an Atari 8bit computer with any kind of limited functionality?  I realize there’s possible analog to digital conversion issues along with the extra keypad pins data that would likely be missing. Just wondering if anybody has ever seen such?  Thx. 

[_The Doctor__]

Not sure what the point would be, you could translate the values and have them trip the directionals so many joysticks already exist that a more responsive and faster.

[pcrow]

This thread, among others, may help in understanding.  The 5200 had essentially the same chipset as the 800 except that it didn't have the PIA chip, so the joystick directions are read as analog inputs that would show up on an 800 as two paddle inputs.  The thread I cited indicates that the keypad is read using the keyboard processing on Pokey; I'm not sure how many wires those signals use, but perhaps they could be read using the four joystick directions to get some meaning.  How many joystick buttons did the 5200 joystick have?  On the 800, the joystick buttons are read by GTIA; I'm not sure how they were processed by the 5200, but you could certainly wire up one joystick button to the regular 800 joystick button.

 

Somewhat related, I've been wondering on the XL if the GTIA inputs for joystick 3 and 4 fire buttons are used for something else or if they're unused.  I'm assuming the paddle 5-8 inputs on Pokey are unused on XL/XE systems, but I would think those two digital inputs might have found some clever use.

[YSG2020]

I figured this to be the case. I see there was a custom analog to digital 5200 9 pin adapter avail by an another user on this board previously but it mapped differently for another console I believe.  I actually really like an upgraded self centering 5200 controller. It’s classic. Would love to use it on my A8s. 

[Rybags]

5200 sticks are analog pots so could likely be directly connected.

The keypad mostly gets scanned by Pokey and is selected by GTIA CONSOL bits which are inputs on the computer, plus the key matrix is wired differently.

In theory a microcontroller could be used in an interface to scan the keys and return codes over the stick direction bits.

 

But either way we'd have a situation where the sticks aren't compatible with any existing game and such efforts would probably be better spent on something else such as Playstation sticks.

A custom OS might be the best way to get over most of the game incompatibility, some buttons could be assigned to functions such as console keys and some passed as commonly used keys such as Esc and Space.