Register Description

4.10.8HDR – Header Type Register

Address Offset:

0Eh

Default Value:

80h

Access:

Read Only

Size:

8 bits

This register identifies the header layout of the configuration space. No physical register exists at this location.

Bit

Descriptions

 

 

7:0

PCI Header (HDR): This field always returns 80 to indicate that Device #0 is a multifunction

 

device. If Functions other than #0 are disabled this field returns a 00 to indicate that the GMCH is

 

a single function device with standard header layout. The default is 80 Reads and Writes to this

 

location have no effect.

 

 

4.10.9SVID – Subsystem Vendor Identification Register

Address Offset:

2C-2Dh

Default Value:

0000h

Access:

Read/Write Once

Size:

16 bits

This value is used to identify the vendor of the subsystem.

Bit

Descriptions

 

 

15:0

Subsystem Vendor ID (SUBVID): This field should be programmed during boot-up to indicate

 

the vendor of the system board. After it has been Written once, it becomes Read Only.

 

 

4.10.10ID – Subsystem Identification Register

Address Offset:

2E-2Fh

Default Value:

0000h

Access:

Read/Write Once

Size:

16 bits

This value is used to identify a particular subsystem.

Bit

Descriptions

 

 

7:0

Subsystem ID (SUBID): This field should be programmed during BIOS initialization. After it has

 

been Written once, it becomes Read Only.

 

 

D15343-003

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Intel D15343-003 manual HDR Header Type Register, ID Subsystem Identification Register