82801DB Datasheet, PDF (255/587 Pages) Intel Corporation – Intel 82801DB I/O Controller Hub 4 (ICH4)

LAN Controller Registers (B1:D8:F0)
7.1.5
7.1.6
7.1.7
7.1.8
REVID—Revision ID Register (LAN Controller—B1:D8:F0)
Offset Address: 08h
Default Value: See Note
Attribute:
Size:
RO
8 bits
Bit
Description
Revision Identification Value — RO. This 8-bit value indicates the revision number for the
7:0 integrated LAN controller. The three least significant bits in this register may be overridden by the ID
and REV ID fields in the EEPROM.
NOTE: Refer to the ICH4 specification update for the value of the Revision ID Register.
SCC—Sub-Class Code Register
(LAN Controller—B1:D8:F0)
Offset Address: 0Ah
Default Value: 00h
Attribute:
Size:
RO
8 bits
Bit
Description
7:0
Sub Class Code — RO. 8-bit value that specifies the sub-class of the device as an Ethernet
controller.
BCC—Base-Class Code Register
(LAN Controller—B1:D8:F0)
Offset Address: 0Bh
Default Value: 02h
Attribute:
Size:
RO
8 bits
Bit
Description
7:0
Base Class Code — RO. 8-bit value that specifies the base class of the device as a network
controller.
CLS—Cache Line Size Register (LAN Controller—B1:D8:F0)
Offset Address: 0Ch
Default Value: 00h
Attribute:
Size:
R/W
8 bits
Bit
Description
7:5 Reserved
Cache Line Size (CLS) — R/W.
00 = Memory Write and Invalidate (MWI) command will not be used by the integrated LAN controller.
01 = MWI command will be used with Cache Line Size set to 8 DWords (only set if a value of 08h is
4:3
written to this register).
10 = MWI command will be used with Cache Line Size set to 16 DWords (only set if a value of 10h is
written to this register).
11 = Invalid. MWI command will not be used.
2:0 Reserved
Intel^® 82801DB ICH4 Datasheet
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