ADDRESS/INTERRUPT TABLES
Page A-2
IRQ
Interrupt Usage
Machine Type
IRQ2
Reserved
PC
IRQ2
Cascade from slave 8259A PIC
AT, PS/2
IRQ3
Serial communications (COM2)
PC, AT, PS/2
IRQ4
Serial communications (COM1)
PC, AT, PS/2
IRQ5
Fixed disk
PC
IRQ5
Parallel printer (LPT2)
AT
IRQ6
Floppy disk
PC, AT, PS/2
IRQ7
Parallel printer (LPT1)
PC, AT, PS/2
IRQ9
Software diverted to IRQ2
AT, PS/2
IRQ10
Reserved
AT, PS/2
IRQ11
Reserved
AT, PS/2
IRQ12
Reserved
AT
IRQ12
Mouse
PS/2
IRQ14
Fixed-disk controller
AT, PS/2
IRQ15
Reserved
AT, PS/2
Table A-2. Commonly Used PC Interrupts