Interrupt Controllers - NEC VERSA UltraLite Service And Reference Manual

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
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1
When enabled.
Name Device
IRQ00 Internal Timer 1
IRQ01 Keyboard
IRQ02 PIC
IRQ08 Real-time Clock
IRQ09 SCI, CardBus, Modem, LAN
IRQ10 Video
IRQ11 Sound
IRQ12 Mouse
IRQ13 Coprocessor
IRQ14 IDE Controller
IRQ15 (Free)
IRQ03 or IRQ04 (Free) Infrared Port
IRQ04 or IRQ03 (Free)
IRQ05 or IRQ09 USB
IRQ06 (Free)
IRQ07 (Free)
1
Specifications 9-7