82801DB Datasheet, PDF (279/587 Pages) Intel Corporation – Intel 82801DB I/O Controller Hub 4 (ICH4)

Hub Interface to PCI Bridge Registers (D30:F0)
8.1.5
8.1.6
8.1.7
8.1.8
RID—Revision Identification Register (HUB-PCI—D30:F0)
Offset:
Default Value:
08h
See Bit Description
Attribute:
Size:
RO
8 Bits
Bit
Description
7:0
Revision Identification Value — RO. Refer to the Intel^® ICH4 specification update for the value of
the Revision ID Register.e
SCC—Sub-Class Code Register (HUB-PCI—D30:F0)
Offset Address: 0Ah
Default Value: 04h
Attribute:
Size:
RO
8 bits
Bit
Description
7:0
Sub Class Code — RO. 8-bit value that indicates the category of bridge for the Intel^® ICH4 hub
interface to PCI bridge. The code is 04h indicating a PCI-to-PCI bridge.
BCC—Base-Class Code Register (HUB-PCI—D30:F0)
Offset Address: 0Bh
Default Value: 06h
Attribute:
Size:
RO
8 bits
Bit
Description
7:0
Base Class Code — RO. 8-bit value that indicates the type of device for the Intel^® ICH4 hub interface
to PCI bridge. The code is 06h indicating a bridge device.
PMLT—Primary Master Latency Timer Register
(HUB-PCI—D30:F0)
Offset Address: 0Dh
Default Value: 00h
This register does not apply to hub interface.
Attribute:
Size:
RO
8 bits
Bit
Description
7:3 Master Latency Timer Count (MLTC). Not implemented.
2:0 Reserved
Intel^® 82801DB ICH4 Datasheet
279