Register Description
R
48 Intel® 82845 MCH for SDR Datasheet
3.5.5 RID—Revision Identification Register (Device 0)
Address Offset: 08h
Default Value: See table below
Access: RO
Size: 8 bits
This register contains the revision number of the MCH Device 0. These bits are read only and
writes to this register have no effect.
Bit Description
7:0 Revision Identification Number. This is an 8-bi t val ue t hat indicates the revision identification
number for the MCH Device 0.
03h = A3 Stepping
04h = B0 Stepping
3.5.6 SUBC—Sub-Class Code Register (Device 0)
Address Offset: 0Ah
Default Value: 00h
Access: RO
Size: 8 bits
This register contains the Sub-Class Code for the MCH Device 0.
Bit Description
7:0 Sub-Class Code (SUBC). This is an 8-bit value that indicat es the category of bridge of the
MCH.
00h = Host bridge.
3.5.7 BCC—Base Class Code Register (Device 0)
Address Offset: 0Bh
Default Value: 06h
Access: RO
Size: 8 bits
This register contains the Base Class Code of the MCH Device 0.
Bit Description
7:0 Base Class Code (BASEC). This is an 8-bit value that indicates the Base Class Code for the
MCH.
06h = Bridge device.