2-20
MS-9149 ATX Server Board
PCI Interrupt Request Routing
The IRQ, abbreviation of interrupt request line and pronounced I-R-Q,
are h ard ware line s ove r whic h d evices ca n s end in terru pt sig nals t o t he
microprocessor. The PCI IRQ pins are typically connected to the PCI bus INT
A# ~ INT D# pins as follows:
Primary IDE Interrupt: IRQ14 (for ICH-HR)
Secondary IDE Interrupt: IRQ15 (for ICH-HR)
PCI-32 IRQ Routing (for ICH-HR)
PCI Device
INT A
INT B
INT C
INT D
PCI32 Slot1
PIRQ#A
PIRQ#B
PIRQ#C
PIRQ#D
PCI32 Slot2
PIRQ#B
PIRQ#C
PIRQ#D
PIRQ#A
PCI32 Slot3
PIRQ#C
PIRQ#D
PIRQ#A
PIRQ#B
VGA
PIRQ#G
82541 GI LAN
PIRQ#H
PDC20378
PIRQ#E
PCIX-64 IRQ Routing (for ICH-HR)
CSA Interface IRQ routing (for Canterwood-ES)
PCI Device
INT A
INT B
INT C
INT D
82547 GI LAN
PIRQ#F
PCI Device
INT A
INT B
INT C
INT D
PCIX-64 Slot1
PX_IRQ#0
PX_IRQ#1
PX_IRQ#2
PX_IRQ#3
PCIX-64 Slot2
PX_IRQ#1
PX_IRQ#2
PX_IRQ#3
PX_IRQ#0
