Specification Sheet

PCI Express* Controller (x16) Registers
376 Datasheet, Volume 2 of 2
Default: 0h
12.23 Interrupt Pin (INTRPIN)—Offset 3Dh
This register specifies which interrupt pin this device uses.
Access Method
Default: 1h
7 4 0
0 0 0 0 0 0 0 0
INTCON
Bit
Range
Default &
Access
Field Name (ID): Description
7:0
0h
RW
INTCON: Interrupt Connection: Used to communicate interrupt line routing
information.
BIOS Requirement: POST software writes the routing information into this register
as it initializes and configures the system. The value indicates to which input of the
system interrupt controller this device's interrupt pin is connected.
Type: CFG
(Size: 8 bits)
Offset: [B:0, D:1, F:0] + 3Dh
7 4 0
0 0 0 0 0 0 0 1
INTPINH
INTPIN
Bit
Range
Default &
Access
Field Name (ID): Description
7:3
0h
RO
INTPINH: Interrupt Pin High:
2:0
1h
RW_O
INTPIN: Interrupt Pin: As a multifunction device, the PCI Express device may specify
any INTx (x=A,B,C,D) as its interrupt pin.
The Interrupt Pin register tells which interrupt pin the device (or device function) uses.
A value of 1 corresponds to INTA# (Default)
A value of 2 corresponds to INTB#
A value of 3 corresponds to INTC#
A value of 4 corresponds to INTD#
Devices (or device functions) that do not use an interrupt pin should put a 0 in this
register.
The values 05h through FFh are reserved.
This register is write once. BIOS should set this register to select the INTx to be used
by this root port.