BIOS Setup
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104-1816CL2NA
IRQ Assignment Table
There are 15 interrupt sources of the system. Some are occupied by the system
devices. Only the ones that are not occupied can be assigned to other devices. ISA
device requests exclusive use of its interrupt. Only the plug and play ISA devices can
be assigned by the UEFI or the OS. And several PCI devices share one interrupt,
which is assigned by UEFI or OS. Interrupt assignment of some devices of X86
platform is shown in the table below, but it does not show the interrupt source
occupied by the PCI devices.
Level
Function
IRQ0 System
Timer
IRQ1
Standard 101/102 Key or Microsoft Keyboard
IRQ2
Reserved
IRQ3
COM 2
IRQ4
COM 1
IRQ5
Reserved
IRQ6
Reserved
IRQ7
Reserved
IRQ8
System CMOS/Real Time Clock
IRQ9 Microsoft
ACPI-Compliant
System
IRQ10 COM4
IRQ11 COM3
IRQ12 PS/2
mouse
IRQ13
Reserved
IRQ14
ATA Channel 0
IRQ15
ATA Channel 1