Appendix B: Programming Interface
Assigned and Available IRQs
Com2
Com1
Real
IDE
Keyboard
Cascade
or
or
Memory
Touch
Floppy
Time
Numeric
Hard
Cardbus
Timer Controller
Interrupt
Com4
Com3
Parity
Screen
SNN
Disk
Clock Coprocessor
Disk
PCI
Control
IRQ0
D
IRQ1
D
IRQ2
D
IRQ3
D
X
X
X
X
IRQ4
X
D
X
X
X
IRQ5
X
X
X
X
X
IRQ6
D
X
IRQ7
X
X
X
X
X
IRQ8
D
IRQ9
X
X
IRQ10
X
X
IRQ11
X
X
IRQ12
X
X
X
X
X
IRQ13
D
IRQ14
D
X
X
IRQ15
X
X
NMI
X
SMI
X
X
D
indicates factory default, X indicates optional or available IRQs
Note: PCI interrupts such as Ethernet, Cardbus, and Video will be mapped to unused ISA
interrupts during PCI enumeration (i.e. power-up).
DMAs
PCS PC-compatible DMA channels:
DMA2
8-bit
Floppy Disk Controller
DMA4
DMA0–DMA3 cascade
DMA5
16-bit
unassigned
DMA6
16-bit
unassigned
DMA7
16-bit
unassigned
34
Planar Clean Screen II PC User’s Manual
CS II Manual LAYOUT#2304 3/25/99 11:16 AM Page 34