National Instruments PXI-8150B, User Manual

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© National Instruments Corporation B-1 PXI-8150B Series User Manual
B
PXI-8150B Series
System Resources
This appendix describes the system resources available on the PXI-8150B
Series embedded computer and where they are allocated. Because PCI is a
relatively new addition to PCs, this appendix describes how PCI interrupts
fit into a PC architecture before listing the devices that use them.
PCI Interrupts
PCI interrupts are more flexible than ISA interrupts because multiple
devices can share these interrupts. PCI interrupts do not actually connect to
the processor directly; they map through ISA interrupts in the system I/O
module. The interrupt handler for a particular ISA interrupt must know if it
will be acknowledging a PCI device.
Resource Tables
The following tables describe where system resources are assigned.
Table B-1 lists how the ISA interrupts are allocated on the
PXI-8150B Series and whether they are driven by a PCI interrupt.
Table B-2 lists DMA channel allocation, and Table B-3 gives the I/O
address map.
Table B-1. PXI-8150B Series ISA Interrupt Resource Allocations
ISA Interrupt PCI Interrupt Device
NMI None Parity
0 None Timer
1 None Keyboard
2 None IRQ Expansion (8-15)
3 None COM2
4 None COM1