Enabling the SNES controller's "extra" buttons...

[Mnemonic]

Hi! New to the boards... just joined. I have a rather unusual SNES controller question that I would like to pose to the tech-savvy members here. In fact, I pretty much joined just to ask this question. :)

As I understand it, a "standard' SNES Controller sends a 16-bit signal to the console on every cycle. Of course, since the standard SNES controller only has 12 buttons, only 12 of those 16 bits are used (the other 4 unused bits are always "high," as no "buttons" exist to ground them).

Well... I was just thinking to myself, were I a game designer, what would stop me from actually assigning "secret" uses to those bits should they ever actually be activated? I mean, were I a game designer I may assign uses to those signals specificly for debugging or playtesting purposes (confident they would never see use outside the design environment, as the controller was physically incapable of activating them).

So, my question is this: Has anyone in this forum ever costom-built a SNES controller to make use of those 4 inputs (that is, included 4 extra buttons)? If so, have any SNES titles been tested with such a controller to see if there actually are any obscure uses associated with these signals?

I just wondering if there may be little "easter eggs" in those SNES games that just haven't been unearthed.

Yeah, I know. Strange question. :)

[joshnickerson]

It's an interesting theory. I remember reading a long while back that the Super Gameboy actually has a few modes that could only be accessed by pressing the L & R buttons in a very specific, quickly timed sequence... and by "quickly", I mean fractions of a second.

EDIT: There was actually a Super Gameboy controller released to take advantage of those secret L & R programs, which would active such enhancements as true slow motion (not rapidly pressing the pause button) and color change without accessing the sub-menu...
http://farm1.static.flickr.com/66/180479214_fd15bd2333.jpg?v=0

[Mnemonic]

There was actually a Super Gameboy controller released to take advantage of those secret L & R programs, which would active such enhancements as true slow motion (not rapidly pressing the pause button) and color change without accessing the sub-menu...

Pretty cool... never even heard about that one, personally.

So anyway, I did some further reading to discover that bit 16 was eventually used for SNES mouse functionality in games that used it (basically, bit 16 "low" means the mouse is in use, activating different protocols). But that still leaves 3 bits never used. If I had the time and/or resources I would be tempted to build something to test out those bits myself.

In hindsight though, I suspect it's also possible that many games require those unused bits "high" in order to confirm the controller is indeed functional (ie: unusual signals from those bits may trigger an error condition). Still has me curious though. Oh well.