Texas Instruments PCI7411, PCI7611, PCI7621 PCI Bus Number Register, CardBus Bus Number Register

4.15 PCI Bus Number Register

The PCI bus number register is programmed by the host system to indicate the bus number of the PCI bus to which the PCI7x21/PCI7x11 controller is connected. The PCI7x21/PCI7x11 controller uses this register in conjunction with the CardBus bus number and subordinate bus number registers to determine when to forward PCI configuration cycles to its secondary buses.

Bit	7	6	5	4	3	2	1	0
Name				PCI bus number
Type	RW	RW	RW	RW	RW	RW	RW	RW
Default	0	0	0	0	0	0	0	0

Register: PCI bus number

Offset: 18h (Functions 0, 1)

Type: Read/Write

Default: 00h

4.16 CardBus Bus Number Register

The CardBus bus number register is programmed by the host system to indicate the bus number of the CardBus bus to which the PCI7x21/PCI7x11 controller is connected. The PCI7x21/PCI7x11 controller uses this register in conjunction with the PCI bus number and subordinate bus number registers to determine when to forward PCI configuration cycles to its secondary buses. This register is separate for each PCI7x21/PCI7x11 controller function.

Bit	7	6	5	4	3	2	1	0
Name				CardBus bus number
Type	RW	RW	RW	RW	RW	RW	RW	RW
Default	0	0	0	0	0	0	0	0
	Register:	CardBus bus number
	Offset:	19h
	Type:	Read/Write
	Default:	00h

4.17 Subordinate Bus Number Register

The subordinate bus number register is programmed by the host system to indicate the highest numbered bus below the CardBus bus. The PCI7x21/PCI7x11 controller uses this register in conjunction with the PCI bus number and CardBus bus number registers to determine when to forward PCI configuration cycles to its secondary buses. This register is separate for each CardBus controller function.

Bit	7	6	5	4	3	2	1	0
Name				Subordinate bus number
Type	RW	RW	RW	RW	RW	RW	RW	RW
Default	0	0	0	0	0	0	0	0
	Register:	Subordinate bus number
	Offset:	1Ah
	Type:	Read/Write
	Default:	00h

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