82801DB Datasheet, PDF (498/587 Pages) Intel Corporation – Intel 82801DB I/O Controller Hub 4 (ICH4)

AC ’97 Modem Controller Registers (D31:F6)
15.1.12
SVID—Subsystem Vendor ID (Modem—D31:F6)
Address Offset:
Default Value:
Lockable:
2C–2Dh
0000h
No
Attribute:
Size:
Power Well:
R/WO
16 bits
Core
The SVID register, in combination with the Subsystem ID register, enable the operating
environment to distinguish one audio subsystem from the other(s). This register is implemented as
a write-once register. Once a value is written to it, the value can be read back. Any subsequent
writes will have no effect. This register is not affected by the D3_HOT to D0 transition.
Bit
Description
15:0 Subsystem Vendor ID — R/Write-Once.
15.1.13
SID—Subsystem ID (Modem—D31:F6)
Address Offset:
Default Value:
Lockable:
2E–2Fh
0000h
No
Attribute:
Size:
Power Well:
R/WO
16 bits
Core
The SID register, in combination with the Subsystem Vendor ID register make it possible for the
operating environment to distinguish one audio subsystem from another. This register is
implemented as write-once register. Once a value is written to it, the value can be read back. Any
subsequent writes will have no effect.
This register is not affected by the D3_HOT to D0 transition.
Bit
15:0 Subsystem ID — R/Write-Once.
Description
15.1.14
CAP_PTR—Capabilities Pointer (Modem—D31:F6)
Address Offset: 34h
Default Value: 50h
Lockable:
No
Attribute:
Size:
Power Well:
This register indicates the offset for the capability pointer.
RO
8 bits
Core
Bit
Description
7:0
Capabilities Pointer (CAP_PTR) — RO. This field indicates that the first capability pointer offset is
offset 50h.
498
Intel^® 82801DB ICH4 Datasheet