PATH
The initial implementation of the PCI bus on Power Macintosh computers supports up to four peer PCI bridge connections to the main processor bus. Figure 1-1 presents a general block diagram of the Power Macintosh system architecture with the PCI bus.
Figure 1-1 PCI system architecture for Power Macintosh
The ARBus (Apple RISC bus) shown in Figure 1-1 is Apple's implementation of the PowerPC processor bus for Power Macintosh computers. Also note that to date no more than two built-in PCI buses have been included in shipping Macintosh configuration.