PCI Bus Switch Provides Integrated PCI-To-PCI Bridging Circuit

Support for Motorola’s PowerQUICC II MPC8260 and PowerPC 750, 740 and 603e is provided by the PowerSpan, a multi-port PCI bus switch that uses a new switching architecture called Switched PCI. The architecture provides integrated PCI-to-PCI bridging, concurrent prefetched reads, and multi-port DMA operation. Targeted applications include networking and telecommunications.Typically, CompactPCI cards use a discrete PCI-to-PCI bridge to interface a local PCI bus to the CompactPCI backplane. An additional bridge is then required to connect the board’s I/O processor to the local PCI bus. The chip’s PCI-to-PCI bridge simplifies this architecture by combining the two bridge devices into one multi-port switch. In addition, the removal of one layer in the bus hierarchy significantly reduces system latencies. The chip is offered in three- and two-port versions.