Review PCI – CMD649 presents PCI Configuration Register, CMD 649, CMD 649 – Setup PIO, CMD 649 – Setup UDMA (Channel x in Ultra DMA IDE/ATA Timing Control Registers, The two registers are UDIDETCR0 for primary channel and UIDETCR1 for secondary channel). | Review PCI – CMD649 Project : Linux Training Engineer : Minh Nguyen Van PCI Configuration Register • Header Type PCI Configuration Register • Vendor ID manufacture of device • Device ID type of device • Subsystem Vendor ID and Subsystem ID Register : the OS distinguish the difference between cards or subsystems. These two registers must contain their assigned values before the system first accesses them PCI Configuration Register • Revision ID Register : Identifies revision number of the device • Base Address Register : PCI Configuration Register • Base Address Register Bits [2:1] : 00b => 32 bit register 10b => 64 bit .