---

PCI USB Controller

The Power Mac G5 CPU uses a PCI USB controller ASIC with one Enhanced Host Controller Interface (EHCI) function and two Open Host Controller Interface (OHCI) functions. The controller has a total of five ports available to support three external USB ports and the internal AGP slot, which goes through the AGP to support the USB hub on the Apple display. The PCI USB controller also supports the Bluetooth and AirPort Express interfaces. If connected to classic-speed USB devices, the two rear panel ports are connected to separate OHCI controllers.

The five USB ports comply with the Universal Serial Bus Specification 2.0. The USB register set complies with the EHCI and OHCI specifications. For more information, see “USB Ports.”

---