Chapter1 Introduction
PXI-846xand NI-CAN for Windows NT 1-2 ni.com
The PXI-8461 physical layer fully conforms to the ISO 11898 physical
layer specificationfor CAN and is optically isolated to 500 V.The
PXI-8460 physical layer conforms to the ISO 11519-2 physical layer
specificationfor CAN and is also optically isolated to 500 V. CAN
interfacingis accomplished using the Intel 82527 C AN controller chip.
The PXI-8461 supports a wide varietyof transfer rates up to 1 Mb/s. The
PXI-8460 supports rates up to 125 kb/s. The PXI-8462 is a dual-speed
board,with port one configured as a high-speed port (ISO 11898), and port
twoconfigured as a low-speed port (ISO 11519-2). The CAN physical
layero n the PXI-8460, PXI-8461, and PXI-8462 can be powered either
internally (from the board) or externally (from the bus cable power). The
powersource for the CAN physical layer for each po rt is configuredwith
aj umper.
PXI-8461 boards are availablewith two physical connecto r types:
•DB-9 D-Sub
•Combicon-stylepluggable screw terminals
PXI-8460and PXI-8462 boards are available with DB-9 D-Sub connectors.
ThePXI-846 xseriesboards use the Real-Time System Integration (RTSI)
busto solve the problem of synchronizing several functions across multiple
boardsto a common tr igger or timing event.The RTSI bus is implemented
byusing the Nation alInstrum ents PXI trigger busto route timing and
triggersignals between the CAN hardware and National Instruments DAQ,
IMAQ,or additional CAN hardware. Although the PXI-846x series board
with RTSIbus is available in a PXI chassis, there are important issues
to considerwhen using it in a CompactPCI chassis. Please refer to
Appendix E, RTSI Bus, for detailed information about the PXI-846x series
RTSIinterface.
The PXI-8460, PXI-8461 and PXI-8462 boards use the Intel 386EX
embedded processorto implement time-critical features provided by the
NI-CAN software.The PXI-846 0, PXI-8461 and PXI-8462 communicate
withthe NI-CAN driver through on-board shared memory and an interrupt.
NI-CAN Software Overview
TheNI-CAN software includes a native, 32-bit multitasking Windows NT
kerneldriver. The NI-CAN softwareis fully integrated into the
WindowsNT operating system. You can configure it through the
WindowsNT Control Panel and uninstall it through the Add/Remove
Programsapplet of the Control Panel.