BIOS Setup
EC3-1816CLD2NA
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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 COM3/4
IRQ8
System CMOS/Real Time Clock
IRQ9
Reserved
IRQ10
Reserved
IRQ11
Reserved
IRQ12 PS/2
Mouse
IRQ13
Numeric data processor
IRQ14
Reserved
IRQ15
Reserved
