B-8 Specifications
Interrupt Controllers
Using interrupts, hardware can request software services. If non-Plug and Play software
is being used, the interrupt may need to be moved for software application or driver
compatibility. Some interrupts cannot be moved. Fifteen interrupts can be used with a
cascade connection of 8259INTC x 2. The table shows default interrupt level
assignments 0 through 15, in order of decreasing priority.
Priority
Name
Device
0
IRQ00
Internal Timer 1
1
IRQ01
Keyboard
2
IRQ02
INT from Controller 2
3
IRQ08
Real-time Clock
4
IRQ09
Reserved for ACPI SCI
5
IRQ10
PC Cardbus/LAN//Video/USB
1
6
IRQ11
Available
7
IRQ12
PS/2 Mouse/NEC VersaGlide
8
IRQ13
Numeric Data Processor
9
IRQ14
Hard Disk Controller 1
10
IRQ15
Not Used
11
IRQ03 or IRQ04
Infrared Port
1
12
IRQ04 or IRQ03
Available
13
IRQ05 or IRQ09
Sound/Modem//PC CardBus
14
IRQ06
Diskette Drive Controller
15
IRQ07
Printer Port (LPT1)
1
When enabled.