genesis adapter schematics

[DarkDraco]

ive been searching online for schematics on how to do this but couldnt find any guides. i found one for parallel somewhere but my port is already in use. can anyone help me out with links to genesis to gameport or genesis to usb? thx in advance

[steveh]

well for usb you would need a encoder chip to convert the signal which you can get from the site i linked in your other thread  there is no way to just wire it to usb   I do remember seeing something that will do the game port.  but that was a while ago.  also i see no need to open a new thread that has to do with the same thing in your other thread

[Crowquill]

Here's one for Atari/C64/etc...

http://www.student.uni-kl.de/~dittrich/joyadapter/index.html

Genesis uses a VERY similar pinout. You might be able to adapt this. My only concern is whether you could get it to register more than the two buttons (b & C if IIRC) that are part of the Atari pinouts (i.e. 7800). It'd be easy to make a Master System adapter, but Genesis is a bit tougher.

Here's some info (including a parallel adapter). http://pinouts.ru/Game/genesiscontroller_pinout.shtml

Somewhere in a box I have an old Kernel Productions Joyport. It's the first console->USB adapter I ever had. It had ports for Playstation, N64, and a 9-pin Atari/Sega port. The thing that impressed me is that you could use all 3 ports at the same time to play 3-player. Unfortunately now, it was built specifically for Mac OS before OS X came out. There was never a driver for use in OS X, so it got packed away. Surprisingly there wasn't a Windows driver that I know of.

Hope some of this helps.

[DarkDraco]

looks like i might have to get the overpriced usb adapter from retrousb. ince my parallel is taken up already. i might just go along with 1 genesis adapter instead of 2

[DarkDraco]

came across this:
gameport pinout: http://www.technick.net/public/code/cp_dpage.php?aiocp_dp=pinconjoy_pc_game
genesis pinout: http://pinouts.ru/Game/genesiscontroller_pinout.shtml

if i match up the pins shouldnt it work? like pin1 on gameport is 5v and pin5 on genesis is 5v, button 1,2,3,4 etc... and if so how will i setup the up down left right? since up/down is pin 1/2 on genesis and on the game port pin 3/4 are just x/y axis.

[Crowquill]

Unfortunately it's a bit more complicated than that. Gameports were built for analog controllers, not digital. So digital controllers have to use strategically placed resistors so that by default it's at 2.5V, and then when you press left it drops to 0V (or 5V when pressing right). This makes the gameport think you're using a potentiometer. There's a lot of good info here:

http://www.epanorama.net/documents/joystick/pc_circuits.html

The other issue is buttons. If you were wiring up an Atari joystick or Master System controller you'd be fine as it uses simple circuits that open and close for each pin much like arcade controls. It also only has one or two buttons. But with Genesis they made some changes to how the pinouts worked. There's an extra identification pin. If the controller has 5V at pin 7, then the two button inputs work as B and C (just like a Master System Controller). But to get A and Start, it grounds pin 7 while sending the button signal.

Six-button controllers use a complex multiplexing system to identify the buttons, so that's definitely not an option. More on these pinouts can be found at the pinouts.ru site.

[DarkDraco]

i think i should just give in and get a genesis>usb adapter for 22$ at retrousb. already saved 90ish making my own nes and snes.
thanks for the links tho, i still read them. circuit work is interesting to learn about

[Crowquill]

It's good to know the theory if nothing else. Part of the reason I'm recalling this stuff so easily is that I was just looking it up earlier in the week figuring out how to adapt Atari Paddle controllers to a Gameport connector.

For those wondering, it'll be easy to wire once I swap the pots out for 100K linear ones.

For $22, it's not worth the hassle (and probably $10 in parts).

[DarkDraco]

yea i tried looking into other methods like making the LPT adapter then using LPT>USB but thy all come out to same price as buying it x.x