BIOS Setup
PPC-1781
· 71 ·
IRQ Assignment Table
There are 15 interrupt sources of the system. Some have been 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 can 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 COM2
IRQ4 COM1
IRQ5 Reserved
IRQ6 Reserved
IRQ7 Reserved
IRQ8
System CMOS/ Real Time Clock
IRQ9 Reserved
IRQ10
COM3, COM4, COM5, COM6
IRQ11
COM7, COM8, COM9, COM10
IRQ12 PS/2
mouse
IRQ13
Numeric data processor
IRQ14 Reserved
IRQ15 Reserved
