Texas Instruments PCI7621 Camera Accessories User Manual


 
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4.12 CardBus Socket Registers/ExCA Base Address Register
This register is programmed with a base address referencing the CardBus socket registers and the memory-mapped
ExCA register set. Bits 31−12 are read/write, and allow the base address to be located anywhere in the 32-bit PCI
memory address space on a 4-Kbyte boundary. Bits 11−0 are read-only, returning 0s when read. When software
writes all 1s to this register, the value read back is FFFF F000h, indicating that at least 4K bytes of memory address
space are required. The CardBus registers start at offset 000h, and the memory-mapped ExCA registers begin at
offset 800h. This register is not shared by functions 0 and 1, so the system maps each socket control register
separately.
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Name CardBus socket registers/ExCA base address
Type RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW RW
Default 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Name CardBus socket registers/ExCA base address
Type RW RW RW RW R R R R R R R R R R R R
Default 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Register: CardBus socket registers/ExCA base address
Offset: 10h
Type: Read-only, Read/Write
Default: 0000 0000h
4.13 Capability Pointer Register
The capability pointer register provides a pointer into the PCI configuration header where the PCI power management
register block resides. PCI header doublewords at A0h and A4h provide the power management (PM) registers. Each
socket has its own capability pointer register. This register is read-only and returns A0h when read.
Bit 7 6 5 4 3 2 1 0
Name Capability pointer
Type R R R R R R R R
Default 1 0 1 0 0 0 0 0
Register: Capability pointer
Offset: 14h
Type: Read-only
Default: A0h