Interrupt And Dma Assignments - IBM 4840-563 System Reference Manual

Interrupt and DMA Assignments

Most IRQ assignments are dynamic because of Plug-and-Play and PCI configuration. However, some are
fixed based on legacy requirements, as shown in the table below. Because the SurePOS 500-XX3 design will
make use of the APIC interrupt controller in the ICH4, there will be 20 interrupts instead of 16 as we had in
the previous designs. The legacy ISA interrupts are the same from 0 - 15, and interrupts 16-19 correspond
to the PCI interrupts INTA, INTB, INTC, and INTD. Thus PCI devices no longer need to take an ISA interrupt
with the APIC design.
IRQ Number
0
1
2
6
8
12
13
14
Below is a list of other resources that will be configured to any available interrupt:
Resource
Serial A
Serial B
LPT1
Ethernet
PCMCIA
Audio
USB
MSR
VFD
Serial C
SurePOS 500 Model XX3 Technical Reference, v 1.3
Resource
System Timer
PS2 Keyboard
Cascade
Floppy Drive
RTC
Mouse
Floating Point
HDD controller
Notes
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Relocate and can be Disabled
Notes...
NS (Not Sharable)
NS
NS
NS, available if floppy not attached or
enabled
NS
NS, available is mouse not attached or
enabled
NS
NS
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