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Using pxi with compactpci, Using pxi with compactpci -2 – National Instruments NI 785xR User Manual

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Chapter 1

Introduction

R Series Intelligent DAQ User Manual

1-2

ni.com

instrument (VI) to the FPGA. Using the FPGA Module, you can
graphically design the timing and functionality of the R Series device.
If you only have LabVIEW but not the FPGA Module, you cannot create
new FPGA VIs, but you can create VIs that run on Windows or a LabVIEW
Real-Time (RT) target to control existing FPGA VIs.

Some applications require tasks such as real-time, floating-point
processing or datalogging while performing I/O and logic on the R Series
device. You can use the LabVIEW Real-Time Module to perform these
additional applications while communicating with and controlling the
R Series device.

The R Series device contains flash memory to store a startup VI for
automatic loading of the FPGA when the system is powered on.

The NI 78xxR uses the Real-Time System Integration (RTSI) bus to easily
synchronize several measurement functions to a common trigger or timing
event. R Series PCI devices access the RTSI bus through a RTSI cable
connected between devices. R Series PXI devices access the RTSI bus
through the PXI trigger lines implemented on the PXI backplane.

Refer to the NI R Series Intelligent DAQ Specifications, available at

ni.com/manuals

, for detailed device specifications.

Using PXI with CompactPCI

Using PXI-compatible products with standard CompactPCI products is an
important feature provided by PXI Hardware Specification Revision 2.1
and PXI Software Specification Revision 2.1. If you use a PXI-compatible
plug-in card in a standard CompactPCI chassis, you cannot use
PXI-specific functions, but you still can use the basic plug-in card
functions. For example, the RTSI bus on the R Series device is available
in a PXI chassis but not in a CompactPCI chassis.

The CompactPCI specification permits vendors to develop sub-buses that
coexist with the basic PCI interface on the CompactPCI bus. Compatible
operation is not guaranteed between CompactPCI devices with different
sub-buses nor between CompactPCI devices with sub-buses and PXI.
The standard implementation for CompactPCI does not include these
sub-buses. The R Series device works in any standard CompactPCI chassis
adhering to the PICMG CompactPCI 2.0 R3.0 core specification.