Ooooh, I'd love the feeling :)
As the wiring for the SMS/GG Plug-in adapter is different to the official Sega Powerbase converter (http://forum.retrode.org/index.php/topic,30.msg257.html#msg257), the SMS/GG Plug-in adapter would not be compatible with the actual Megadrive/Genesis hardware. Now correct me if I am wrong, but I'm pretty sure the pause button just paused the game that you were playing, so unless there could be some way to set the button to communicate with the emulator (somehow linked in with the controller support?), I'm not sure what purpose it would serve.
Agree, what would that be good for? Your Master System emulator already has a pause function, doesn't it?
I agree it would be an interesting feature to add to the authenticity slightly, but a bit of a pointless one for practical use in my opinion (since you have a keyboard right in front of you in all likelihood so can map a key there to a pause key) - and if you still really want it for some reason, Matthias could possibly include support for the PBC pause button IF he decides to implement general PBC support*. That would, in my opinion, be a better solution than making the adapter in general more expensive for the sake of a pause button that few will use.
*PBC support would be a nice feature, with (I'm guessing, I haven't seen the code!) relatively little effort involved (assuming there aren't any complications, should just be remapping virtually of address lines to different address lines, etc.), though might of course diminish sales of the SMS/GG adaptors (depending on how many people who want one of the adaptors already have a PBC!). The pause button on the PBC, if it is even possible, would obviously be harder; if it is supported, I think it should be done in tandem with wider in-cart-controls support such as J-Carts (and any other examples if they exist, which I don't think they do); I believe specifications on how these J-carts worked were at some point posted in the comments section, maybe by me (I can't remember!) And, speaking of J-Carts, is there any chance of making sure games that have an empty name field (eg Micro Machines '96) don't have filenames that start with a dot, because that makes them hidden on Unix-based OSes, causing much confusion. Sorry for the huge tangent.
@Muzer: Congratulations, you just qualified to set up and maintain a feature wishlist ;D I often find myself having a hard time locating all those things that are spread out all over the place, so it would be nice to collect them in a single spot. Would you care to give it a try? Just start a new thread (will be stickied), and try to gather suggestions (given via reply, and stuff you may run into elsewhere) in the root post. A simple unnumbered list should do.
Thanks,
Matthias
Sure! Glad to! Will do...
Support for the Power Base will sure be fine with me. I thought the form factor of the powerbase made it impossible to use on the Retrode.