Since some people on the forums (myself included) mentioned that they are not able to use the retro-bit controllers, or any other generic usb gamepad for that matter, to navigate in the game room / game hub, I decided to look in to this.

I acctually figured out a way to dio this, BUT this method also has it's drawbacks (please see the Drawbacks section of the Guide to determine if it is even worth it, for you presonally, to try to apply the settings in this guide)

You will have to follow this guide step by step (at least at first) otherwise you might experience some unexpected or wierd controller behavior which will require resetting the steam controller configuration. (Please refer to the Resetting the Steam Controller Configuration Settings section of this guide for detailed information)

This is very important, since this is where your controller configuration is saved. You will need this if you screw up the configuration (and you probably will) and will have to reset the steam controller configuration. (Detailed information on reseting the steam controller settings is located in the Resetting the Steam Controller Settings section of this guide)

What this basically does, is map a "generic" usb controller to an x-box controller input layout! This means every single game on steam will recognize your retro-bit controller as such! This could be already the point where a lot of people will say "screw this" (myself included). More information on this in the Drawbacks section.
If you still wish to continue lets get started then...

Just for reference this is my original retro-bit sega genesis controller mappings in the game room.

This is the mapping I use after the controller configuration through big picture mode.











Now lets get to the actual configuration...














You can also just start the big picture mode and navigate to controller configuration from there, but this seems to be the more direct way

If someone should be able to do the rest of the setup wihtout activating this option, please let me know! For me it was the ONLY way to make both the Genesis / Mega Drive or the Saturn USB controller to wrk properly. Also from here on you can use the Genesis / Mega Driver USB Controller to navigate in Big Picture mode, but be carefull since it uses the X-Box Controller layout and the functions permanently assigned to its buttons!

The default assignement should look something like this ... This NOT GOOD at all










You should change it to something like this (D-Pad Mapping is very important here!):











IMPORTANT: Do NOT try to map the separate D-Pad "Buttons" to the D-Pad of the X-Box Controller layout! The D-Pad of the Genesis USB Pad is only being read out as Axis not individual buttons - you MUST assign the axis to the left stick axis of the X-Box Controller. (If this different for someone please also let me know, so I can update this information)

Click "Save"










IMPORTANT: Whatever you do DO NOT select the X-Box One or the X-Box 360 for Controller Type you MUST use "Generic Gamepad" !!! At least this is how it was for me, selecting any other option resulted in d-pad/axis assignment going ape s**t on me and I had to reset the Steam Controller Settings through the config.vdf file and start over. I will elaborate on that later on...
Also do not try to assigned the buttons one after the other just by pressing them on your Genesis / Mega Drive USB Controller because it already utilizes the X-Box Controller layout and the function that are permanently assigned to it's button on Big Picture Mode, so that you could accidently exit the configuration before completing the mappings (especially assigned the axis) and the controlls go ape s**t on you again.












After saving the configuration the "Generic Gamepad : Generic Gamepad" entry might disappear for a short time and come back at which point you should get this messages (or you might now - not sure on that)







IMPORTANT: At least in my case, the Big Picture Mode itself got minimized which I didn't notice so I just clicked on close on the message, but this was not good, since the new configuration only gets fully applied if you also go back to Big Picture Mode and click on "back" to exit!










Somewhere during the Splash Screens you should get this message. This means that all of the above was done right and the controller can now be used to navigate the game room, but stick to mouse/keyboard controlls first until you are done with buttons assignment within the game room as well!











I already included the screenshot of my bindings in the beginning of the guide, here it is again including the explanation why something like this should be used:











I assigned the Mode Button of the Genesis / Mega Drive USB Controller to the "Back Button" of the X-Box Controller layout, this was done purposefully because the "Back Button" is used to actually go back in the emulator and game room ("press and hold to go back" if you know what I mean). This means that this button is better left unassigned in the emulator mappings, for obvious reasons!
I also assigned the shoulder buttons to "rewind" and "frame skip" in the emulator mappings. And yes I know this way I sacrificed the use of the actual mode button within the game, but since it is not used by a lot of games (I am not even sure which games from this particular collection do use it) I think I am ok with that - this is just my personal preference so feel free to do a different button mapping, only the assignments in big picture mode were crucial for the functionality, within the emulatior only the usage of the controller button which was asigned to the "back" button of the X-Box Controller layout on Big Picture mode presents a slight issue as holding it would exit the game.
Here is an example of the functions within the game room using the mappings I applied:











The A-Button would be the A-Button of the X-Box layout, B would also be B but C-Button would be the Y-Button and X-Button would be the X-Button - of course you can adjust first the mappings in Big Picture mode and then in the Emulator for assignment to be more intuitive like A,B,X,Y actually being the corresponding buttons on the Genesis / Mega Drive pad, this "work" is up to you and if you do screw up you can alway use the guide to reset the Big Picture settings provided in the separate section of this guide ;)













I would just hold mode button to go back...













and then press the A-Button to continue playing or the the B-Button to go back to the room, or the C-Button to go back to full screen, or X-Button to go the Save/Load menu

well if you are reading this, than you probably screwed somewhere, don't worry I had to apply this a lot of times until I got the procedure down ;)

As I mentioned before the controller configuration is stored in the config.vdf file which is found in the config sub folder of the Steam installation folder.

The controller assignment and mapping part of it would be this:
ususally found in the bottom part of the file. This example is actually a working configuration for my Genesis / Mega Drive USB Controller.

If it is this simple, why the guide for a reset you might ask...

Well first of all if you save the controller configuration with the d-pad axis still assigned to the D-Pad butons of the X-Box Controller layout in Big Picture mode, the controlls will probably go ape s**t on you, meanning the D-Pad Down and Left for example being pressed permanently.
Doesn't sound that bad at first, BUT when I simply tried to reassign them it didn't remove the binding to the D-Pad but simply added the assignement to the left analog stick which made things worse! After trying for several time I got the buttons and axis assigned to functions several times, the above config part was almost two pages long...

But you know where the settings and assignment are located, why not just reassign them within the config file yourself???

Yes this may be possible for some of you but for me changing the settings and mappings within the file and then restarting steam resulted in my changes beeing discarded and the mappings I applied through Big Picture Mode being restored. I have no Idea as for how or why or if it even going be an issue for others, but in my case it was!

So here is the procedure to really reset the settings made on big picture mode:

1. open up controller settings for Big Picture mode
   
2. disable the "Generic Gamepad Configuration Support" option (also all other option if activated)
   
3. exit Steam and disconnect the controller
   
4. open the config.vdf file and delete SDL_GamepadBind part (only leave the } at the end if the SDL_GamePadBind entry is the last one in the file since it belongs to an entry located somewhere above!
   
5. save the file (this is why a back up made before starting this whole project would be welcome by now as you could go back to the state before fiddling around with the Big Picture Controller Settings)
   
6. start Steam and connect the controller (now you should be able to start over

Also another note:

I didn't back up the file before fiddling around in Big Picture mode and after I do the above steps, I can get start over with the controller configuration, but Steam is apparently recognizing my Genesis / Mega Drive USB controller as a "Retrolink SNES Controller"... This is the part which is added to the config.vdf after resetting the moment I plugged the controller back in:


I don't really mind it since it still restores the configuration state before I first opened up the Big Picture controller settings, even the original controller bindings within the Sega Genesis Classics game room are restored back, but I am wondering if it is the result of fiddling around with the Big Picture Controller settings, or if it was like this from the moment I first connected the retro-bit Genesis controller to my system and started up Steam... anyone figures this out please let me know!

Activating the Generic Gamepad Support in the Big Picture Mode and saving the configuration permanently maps your Sega Genesis / Mega Driver USB Controller or any other custom/generic USB Game Pad to an X-Box Controller input layout, which doesn't even sound that bad, since you will be able to use this controller even in games which would not recognize the controller before.

Maybe for some of you this would even seem to be a great improvement BUT this also means, ALL input settings / bindings in ALL the games made prior to this settings will stop working!
You will at least have to rebind / reconfigure the controller in all the games you used it in!

Even this might not be so bad for a lot of you and isn't actually that bad for me as well but for example I also use the Sega Saturn USB controller to play Spelunky with a very specific button binding, I actually had to use the JoyToKey tool to be abe to use the controller in this game to begin with, since it was otherwise not recognized by the game.
So not having to use this tool is actually an improvement for you, you might say...
Unfortunately the oposite is the case... I can not recreate the same button layout as before wihtout changing the button bindings in the Big Picture mode, which results in messing up the bindings for example in the Sega Classics Collection (as well as other games) due to the fact the bindings and settings in the Big Picture mode are global, changes there affect the bindings made in all the games.

So bottom line is:
I would either have to change the bindings on Big Picture Mode every time I play a different game,

or I would have to make a copy of the config.vdf file for each new game specific configuration I make on Big Picture mode
(I am not even sure this is gonna work, since Steam seems to restore all the controller settings back if I divert from the Reset Procedure even on one step.. I would have to look in to this)

or I haave to spend some (or maybe a lot of) time to figure out one proper binding on Big Picture mode which would suit all the games I play
(something tells me this is not gonna happen...)

Any input on this would be greatly appreciated, maybe some one out there has more time and perseverance than I do and will figure out a better approach, in which case I would be more than happy to edit/update this Guide.

I tried to keep this as simple as possible, emphasis being on tried...
I hope some one still finds this guide usefull and helpfull though.

P.S. someone really needs to proof read all this crap and get back to me, english is not my native language and I already found like 20 spelling erros on the first read through ;)