Specifications
6–8
System interrupt specifications
Hardware IRQ
System function
IRQ0
System timer
IRQ1
Standard 101-/102-key or Microsoft Natural Keyboard
IRQ2
Cascaded
IRQ3
Intel 82801DB/DBM USB2 Enhanced Host Controller—24CD
IRQ4
COM1
IRQ5*
Conexant AC—Link Audio Intel 82801DB/DBM SMBus Controller—24C3 Data
Fax Modem with SmartCP
IRQ6
Diskette drive
IRQ7*
Parallel port
IRQ8
System CMOS/real-time clock
IRQ9*
Microsoft ACP-compliant system
IRQ10*
Intel USB UHCI controller—24C2
Intel 82852/82855 GM/GME Graphic Controller
Realtek RTL8139 Family PCI Fast Ethernet Controller
IRQ11
Intel USB EHCI controller—24CD
Intel USB UHCI controller—24C4
Intel USB UHCI controller—24C7
Intel Pro/Wireless 2200BG
TI OHCI 1394 host controller
TI PCI1410 CardBus controller
IRQ12
Synaptics PS/2 TouchPad
IRQ13
Numeric data processor
IRQ14
Primary IDE channel
IRQ15
Secondary IDE channel
IRQ16
Intel ICH9 Family USB universal host controller 2937
Mobile Intel 4 Series Express Chipset Family
IRQ17
High definition audio controller
Intel ICH9 Family USB universal host controller 2938
Marvell Yukon 88E8072 PCIE-gigabit Ethernet controller
IRQ18
Intel ICH9 Family USB universal host controller 2939
Intel ICH9 Family USB universal host controller 2936
IRQ19
Intel ICH9 Family USB2 enhanced controller 293C
IRQ20
Intel ICH9 Family USB2 enhanced controller 293A
Intel ICH9 Family USB universal host controller 2934
IRQ21
Intel ICH9M-E/M SATA AHCI controller
IRQ22
Intel ICH9 Family USB universal host controller 2935
*Default configuration; audio possible configurations are IRQ5, IRQ7, IRQ9, IRQ10, or none.
✎
PC Cards may assert IRQ3, IRQ4, IRQ5, IRQ7, IRQ9, IRQ10, IRQ11, or IRQ15. Either the infrared or the serial port
may assert IRQ3 or IRQ4.
✎
For operating systems after Windows 2000, APIC (Advanced programming interrupt controller) is used.