The BRIDGE ASIC is used as the PCI hostbridge in the SGI IP27 family of machines, and also on SGI IP30. It interfaces between the internal Crosstalk connect one the one side and the 64-bit, 33MHz PCI bus on the other side. It supports 32-bit PCI cards by providing an address translation mechanism allowing 32-bit PCI cards to access the entire 64-bit address space of the system. BRIDGE also allows to specify a few attributes in 64-bit DMA addresses rsp. the address translation tables allowing to maximize performance.