Where can I find pinouts for the various ports on my Mac?
Apple has a Service Source PDF called “Ports and Pinouts” but most of us don’t have access to Service Manuals. So check out this Hardware Tech Note, number 19. It has pinout information for most Mac ports. If that doesn’t answer your question, maybe this German site will. For more information about 68K pinouts, see the pinouts page of this FAQ (requires Internet connection; contains images).