BIOS Setup
· 36 ·
EC3-1820V2NA
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.
Interrupt No.
Device Description
IRQ0 System
timer
IRQ1
PS/2 standard keyboard
IRQ2 Reserved
IRQ3
COM2
IRQ4 COM1
IRQ5 Reserved
IRQ6 Reserved
IRQ7 Reserved
IRQ8
High precision event timer
IRQ9 Reserved
IRQ10 COM3
IRQ11 COM4
IRQ12
PS/2 compatible mouse
IRQ13 Reserved
IRQ14 Reserved
IRQ15 Reserved