The Short Version: On a Mac it seems that only the port on the right can be used but Windows users didn’t report the same problem. I had a calibration issue the first time I used the adapter with an original N64 controller but the next time I fired up Sixtyforce I set the axis deadzone to zero and it worked perfectly.
For Valentine’s Day my wife bought a couple of items from my Amazon Wish List along with some other cool gifts. One of the items was a May Flash N64 Controller Adapter for USB. While I haven’t had a chance to really put it to a good test I did get some time to hook it up to an N64 controller that I bought yesterday from a pawn shop for $5.
The USB adapter includes two N64 controller ports and it works with Windows and Mac OS X. There aren’t any drivers available. It seems to work via the standard HID interfaces.
Note that there is one important caveat for use with a Mac. So far it only appears to work with one controller. Specifically, only the N64 port on the right. I don’t know if this is specific to the OS X drivers or if it’s a software compatibility issue. Amazon review comments hint that it may just be a general problem when using the adapter with OS X. I’ve used it with Sixtyforce and that’s the only N64 emulator I’ve used on a Mac.
In Sixtyforce the button mappings worked well. I did have problems with the calibration of the stick on the controller. Its resting position caused the character to constantly move forward. At this point I don’t know if it’s just a sign of an old controller or if there’s something I can do on the OS side to fix the alignment. I’ll keep toying with it, but I don’t think it’s a problem with the adapter itself.
Overall, this is a cool little device. I also have their SNES adapter but I haven’t acquired SNES controllers yet.
Updated 02/18/2012: I tried the controller again and set the axis deadzone to zero in Sixtyforce. This time it worked perfectly.