Genesis work on atari, atari don't work on genesis?

[gliptitude]

Unmodified Sega Genesis controllers work on Atari 2600. So I became really excited when it occurred to me that 2600 controllers might also work on Sega Genesis. Does anyone know this to not be the case, or have some explanation?

Of course the Atari controllers don't have enough buttons to play most Sega games. But I imagine there are some Sega games that really only require one button, (Sonic the Hedgehog as I remember?). .. But more pertaining to my needs, I recently acquired a VecAdapt unit for using Genesis controllers on Vectrex. After reading about someone else using a PSX to Genesis adapter to use PS2 controllers on Atari, it occured to me that I might be able to use my favorite 2600 controller to play a few Vectrex games!

It didn't work. There is some response from the joystick but it is not the correct one. The stick seems to constantly signal LEFT and every directional input seems to signal multiple directions. Pressing the fire button seems to correspond to two different Vectrex/Sega buttons at the same time.

I don't have a Sega Genesis.

I have a rare 2600 joystick that I love and wish I could use on my other favorite consoles.

[gliptitude]

Well i tested the same setup using the Test Cart to monitor joystick input.

Atari joystick to VecAdapt to Vectrex yields constant maximum LEFT and DOWN when nothing is pressed. All directions are triggered appropriately when joystick is operated, but it always returns to max Left/Down when static. Pressing the Fire button yields Vectrex buttons 3 and 4 simultaneously, or 1 and 2 if the button swap is switched on the VecAdapt.

What was most interesting is the that the VecAdapt by itself, (with no controller plugged into it) also yields constant max Left/Down.

When a Sega Genesis controller is plugged into the VecAdapt the constant Left and Down goes away and the static state is what you would expect, no input.

.. I bought two VecAdapts and I am tempted to pry one open and mod it for VCS controllers if it looks like that might be a practical mod.

[sj]

Don't use your knife and fork. I remember the radiator pics...

SPOILER: Click to show

{What I really mean is...}Good luck with that.