JG82855GMESL7VN Datasheet, PDF (119/213 Pages) Intel Corporation – Intel® 855GM/855GME Chipset Graphics and Memory Controller Hub (GMCH)

Register Description
R
4.11.13
SVID – Subsystem Vendor Identification Register (Device
#2)
Address Offset:
Default Value:
Access:
Size:
2C−2Dh
0000h
Read/Write Once
16 bits
Bit
Description
15:0 Subsystem Vendor ID: This value is used to identify the vendor of the subsystem. This register should
be programmed by BIOS during boot-up. Once written, this register becomes Read Only. This register
can only be cleared by a reset.
4.11.14
SID – Subsystem Identification Register (Device #2)
Address Offset:
Default Value:
Access:
Size:
2E−2Fh
0000h
Read/Write Once
16 bits
Bit
Description
15:0 Subsystem Identification: This value is used to identify a particular subsystem. This field should be
programmed by BIOS during boot-up. Once written, this register becomes Read Only. This register can
only be cleared by a reset.
4.11.15
ROMADR – Video BIOS ROM Base Address Registers
(Device #2)
Address Offset:
Default Value:
Access:
Size:
30−33h
00000000h
Read Only
32 bits
The IGD does not use a separate BIOS ROM, therefore this register is hardwired to 0’s.
Bit
31:18
17:11
10:1
0
Description
ROM Base Address⎯RO
Address Mask⎯RO: Indicates 256-kB address range.
Reserved
ROM BIOS Enable⎯RO: Indicates ROM not accessible.
Datasheet
119