For more information about USB on the Macintosh computer, refer to Apple Computer’s Mac OS USB DDK API Reference. Information is also available at
http://developer.apple.com/documentation/Hardware/DeviceManagers/usb/usb.html
USB game controllers are supported by the InputSprocket component of the Apple Games Sprockets software architecture. InputSprocket software and information about the InputSprocket APIs can be found at
http://developer.apple.com/games/
For full specifications of the Universal Serial Bus, you should refer to the USB Implementation Forum on the World Wide Web, at:
http://www.usb.org/developers/docs