Avago Technologies LSI53C1020 - Manual (Page 95)

PCI Configuration Space Register Descriptions 4-17
Version 2.4 Copyright © 2001–2004 by LSI Logic Corporation. All rights reserved.
Register: 0x3C
Interrupt Line
Read/Write
Interrupt Line [7:0]
This 8-bit register communicates interrupt line routing
information. Power-On-Self-Test (POST) software writes
the routing information into this register as it configures
the system. This register indicates the system interrupt
controller input to which the PCI function’s interrupt pin
connects. System architecture determines the values in
this register.
Register: 0x3D
Interrupt Pin
Read Only
Interrupt Pin [7:0]
The encoding of this read-only register indicates which
interrupt pin the function uses. The value for the PCI
function is 0x01, which indicates that the PCI function
presents interrupts on the INTA/ or ALT_INTA pins. The
Interrupt Request Routing Mode bits, bits [9:8] in the
Host
Interrupt Mask register, determine if the function presents
interrupts on INTA/, ALT_INTA, or both.
7 0
Interrupt Line
0 0 0 0 0 0 0 0
7 0
Interrupt Pin
0 0 0 0 0 0 0 1