Genesis 6-button controller compatibility

[Harrison]

So I tried using a 6-button genesis controller made by Hyperkin with my 2600, and it's not working right. Left on the d-pad does not respond, but the other directions work. The B button works fine, though I've noticed if you hold down any other button for a few seconds, the controller will stop responding altogether until the power is turned off. You don't use those buttons anyway, but I found it odd. Do third party genesis controllers tend to have issues like this? Are there any brands with known issues that should be avoided? I haven't tried an official Sega 6-button on the 2600, so I'm not actually sure if the 6-button works to begin with.

Edited December 2, 2016 by Harrison

[alex_79]

I guess the controller doesn't get proper power from the console.
It's a fortunate circumstance that Genesis controllers work on the Atari, because the port pinout is slightly different. The main difference is that power is on pin 7 on the Atari, while is pin 5 on the Genesis. Genesis' pin 7 is a "select" line which determines what buttons or direction will appear on the data pins depending if it's in high (+5v) or low (0v) state.
The fact is that the original controllers happen to work even if power is applyed to the select line instead of the proper pin 5. (This is not an intended behaviour, it's just due to the internal contruction of the IC used to "multiplex" the many buttons and directions to the fewer pins available on the port).
Probably the 3rd party controller you have has different internals which don't show this "quirk" making it incompatible with the Atari.

If this is the problem, it can be fixed this by either modifying the controller or building a pass-through adapter. If you modify the controller it won't be compatible with the genesys anymore, so I prefer the adapter solution.

To modify the controller you must solder a jumper between the pads where pin 7 and 5 from the plug are connected to the controller pcb, and then cut the wire going to the plug's pin 5. After that, the controller won't be compatible with the genesis anymore.

The pass-through adapter only consists in male and a female 9-pin connectors and some wires: Connect pin 7 from the female connector (the one that goes into the Atari port) to both pins 7 and 5 or the male one, then connect pins 1, 2, 3, 4, 6, 8, 9 to the corresponding ones between the two connectors. This require more soldering but doesn't modify the controller, so it can still be used with the genesis.

[MaximRecoil]

I haven't tried an official Sega 6-button on the 2600, so I'm not actually sure if the 6-button works to begin with.

 

It definitely does. I used a pair of them with an Atari 7800 (for games which only use one button) and an Atari 2600 console before I converted a pair of NES controllers to 7800/2600 controllers.

[Harrison]

Thanks guys. That clears things up a lot.

[Adam 12]

I just attempted this mod on my Hyperkin 6 Button, which shows the same behavior when plugged into my Atari.

 

I dont have soldering ewuipment, so i went at it a bit differently.  I stead of soldering pay 5 to pad 7 in the controller, and cutting wire 5, I cut wire and spliced it to wire 7, while leaving 7 connected.

 

This may be incorrect.  But, in my no -mechanical mind, it seems flow of current should work the dame with either solution.

 

Or, perhaps i misunderstood the directions completely.

 

In any case, after the mod, testing still showed improper behavior.

 

Any insight?  I just want to rewire this to be a pure Atari controller, no need to worry about working o  a Genesis anymore.

 

What if i rewired it to change all the pinouts to their Atari equivelents, would that work at all?

 

The way I did the mod is fully reversable.  Rewiring the whole thing is doable easily as well .