The TC9021A/TC9020A can operate in systems utilizing a 32-bit or 64-bit wide PCI bus running at 33MHz or 66 MHz. The TC9021A/TC9020A is compliant with PCI specification revision 2.2, and is capable of accessing up to 1 terabytes of system memory via the PCI Dual Address Cycle (DAC) command. Advanced PCI commands, such as Write and Invalidate, Read Line, and Read Multiple, are also implemented to further improve sys-tem performance. Bus Master Dual Channel DMA