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The PCI host bridge generates configuration cycles in an indirect manner, similar to mechanism #1 suggested in the PCI specification, using configuration address and configuration data registers to create a single configuration cycle on the PCI bus. The system determines which PCI host bridge and bridge area to use when accessing each specific card. Because configuration cycles must go through a programming interface, high performance interfaces should try to use the PCI memory space instead of configuration space. The programming interface for configuration cycles is described in Configuration Space Cycle Generation.