Q: Why do the oldest PCI Macintoshes (such as the 9500) not recognize a CardBus controller?

A: Because CardBus hadn't been invented yet. Each device must fall into a "class code" model. When the 9500 went GM, there was no class code for CardBus; hence, these machines do not recognize a CardBus device. However, the device will appear in the device tree, but will not be recognized by the Mac OS as CardBus.

Developer Documentation | Technical Notes | Development Kits | Sample Code