82801BA Datasheet, PDF (371/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

USB Controller Registers
11.1.11
SID—Subsystem ID (USB—D31:F2/F4)
Address Offset:
Default Value:
Lockable:
2Eh–2Fh
00h
No
Attribute:
Size:
Power Well:
RO
16 bits
Core
Bit
Description
Subsystem ID (SID)—R/Write-Once. The SID register, in combination with the SVID register,
15:0 enables the operating system (OS) to distinguish subsystems from each other. The value returned
by reads to this register is the same as that which was written by BIOS into the IDE_SID register.
11.1.12
INTR_LN—Interrupt Line Register (USB—D31:F2/F4)
Address Offset:
3Ch
Default Value:
00h
Attribute:
Size:
R/W
8 bits
Bit
Description
7:0
Interrupt Line—R/W. This data is not used by the ICH2. It is to communicate to software the interrupt
line that the interrupt pin is connected to.
11.1.13
INTR_PN—Interrupt Pin Register (USB—D31:F2/F4)
Address Offset:
Default Value:
Default Value:
3Dh
Attribute:
Size:
Function 2: 03h(82801BA ICH2)
04h (82801B AM ICH2-M)
Function 4: 03h (both ICH2 and ICH2-M)
RO
8 bits
Bit
Description
7:3 Reserved.
Interrupt Pin—RO. The value of 03h in Function 2 indicates that the ICH2 will drive PIRQD# as its
interrupt line for USB Controller 0 (ports 0 and 1).
2:0 _{The value of 03h in Function 4 indicates that the ICH2 will drive PIRQC# as its interrupt line for USB}
Controller 1 (ports 2 and 3). However, in the ICH2 implementation, when the USB Controller 1
interrupt is generated PIRQ[H]# will go active, not PIRQ[C]#.
11.1.14
SB_RELNUM—Serial Bus Release Number Register
(USB—D31:F2/F4)
Address Offset:
60h
Default Value:
10h
Attribute:
Size:
RO
8 bits
Bit
Description
Serial Bus Release Number—RO.
7:0
10h = Indicates that the USB controller is compliant with the USB specification release 1.0.
82801BA ICH2 and 82801BAM ICH2-M Datasheet
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