Well, it almost worked

[arromdee]

Attempting to use a 6 button PCE pad on a TG-16.

It turns out there's an existing cable that by pure chance happens to have the correct 8 pin DIN and mini-DIN plugs (it also requires a F/F gender changer).  It was an interesting theory, and I was hoping that the pinouts on a DIN and mini-DIN were standardized enough that it might work, but it doesn't.

Hacking the cable is beyond my expertise, though I'd be curious if anyone has tried it.

[BigT]

You'd have to test how the cable is wired.

Here are the large and mini-din pinouts:
http://www.gamesx.com/controldata/turbocont.htm

You can test continuity with a simple continuity tester or a multimeter.

If the connectors are molded, rewiring may be a bit of a pain; it may be easier to hack together a M-F adapter (or in your case the F-F gender changer) to fix the pinout.

[arromdee]

I don't own any electronics equipment and the only thing I ever did that's close to an electronics project was putting a country switch in a Mega Drive.

I suppose I'll just have to find a spare TG-16 pad and switch the plugs.