82801BA Datasheet, PDF (253/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

Hub Interface to PCI Bridge Registers (D30:F0)
8.1.6
8.1.7
8.1.8
8.1.9
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. This 8-bit value indicates the category of bridge for the ICH2 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. This 8-bit value indicates the type of device for the ICH2 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 Count. Not implemented.
2:0 Reserved.
HEADTYP—Header Type Register (HUB-PCI—D30:F0)
Offset Address: 0Eh
Default Value: 01h
Attribute:
Size:
RO
8 bits
Bit
Description
7 Multi-function Device—RO. This bit is 0 to indicate a single function device.
6:0
Header Type—RO. 8-bit field identifies the header layout of the configuration space, which is a PCI-
to-PCI bridge in this case.
82801BA ICH2 and 82801BAM ICH2-M Datasheet
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