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Appendix
MB991AF
User’s Manual
77
B.
Interrupt Request Lines (IRQ)
Peripheral devices use interrupt request lines to notify CPU for the service
required. The following table shows the IRQ used by the devices on board.
Level
Function
IRQ 0
System timer
IRQ 1
Standard PS/2 Keyboard
IRQ 3
Communications Port (COM2)
IRQ 4
Communications Port (COM1)
IRQ 5
Communications Port (COM3)
IRQ 7
Communications Port (COM4)
IRQ 8
System CMOS / real time clock
IRQ 11
Intel(R) Xeon(R) E3 - 1200/1500 v5/6th Gen
Intel(R) Core(TM) Gaussian Mixture Model -
1911
IRQ 11
Intel(R) 100 Series / C230 Series Chipset
Family SMBus - A123
IRQ 11
Intel(R) 100 Series / C230 Series Chipset
Family Thermal subsystem - A131
IRQ 12
Microsoft PS/2 Mouse
IRQ 13
Numeric data processor
IRQ 14
Motherboard resources
IRQ 16
Intel(R) Serial IO I2C Host Controller - A160
IRQ 16
High Definition Audio Controller
IRQ 18
Communications Port (COM7)
IRQ 18
Communications Port (COM8)
IRQ 18
Communications Port (COM9)
IRQ 18
FINTEK Pcie To Serial
IRQ 18
Communications Port (COM6)
IRQ 19
Intel(R) Active Management Technology -
SOL (COM5)