Chapter 1 Introduction
© National Instruments Corporation 1-5 NI 7831R User Manual
The FPGA logic provides timing, triggering, processing, and custom I/O
measurements. Each fixed I/O resource used by the application uses a small
portion of the FPGA logic that controls the fixed I/O resource. The bus
interface also uses a small portion of the FPGA logic to provide software
access to the device.
The remaining FPGA logic is available for higher level functions such as
timing, triggering, and counting. The functions use varied amounts of logic.
You can place useful applications in the FPGA. How much FPGA space
your application requires depends on your need for I/O recovery, I/O, and
logic algorithms.
The FPGA does not retain the VI when it is powered off, so you must reload
the VI each time you power on. You can load the VI from onboard flash
memory or from software over the bus interface. One advantage to using
flash memory is that the VI can start executing almost immediately after
power up, instead of waiting for the computer to completely boot and load
the FPGA. Refer to the LabVIEW FPGA Module User Manual for more
information about how to store your VI in flash memory.

Reconfigurable I/O Applications

You can use the LabVIEW FPGA Module to create or acquire new VIs for
your application. The FPGA Module allows you to define custom
functionality for the R Series device using a subset of LabVIEW
functionality. Refer to the FPGA Module examples located in the
<LabVIEW>\examples\FPGA directory for examples of FPGA VIs.
Software Development
You can use LabVIEW with the LabVIEW FPGA Module to program the
NI7 831R. To develop real-time applications that control the NI 7831R,
you can use LabVIEW with the LabVIEW Real-Time Module.

LabVIEW FPGA Module

The FPGA Module enables you to use LabVIEW to create VIs that run on
the FPGA of the R Series device. Use the FPGA Module VIs and functions
to control the I/O, timing, and logic of the R Series device and to generate
interrupts for synchronization. Refer to the LabVIEW FPGA Interface User
Guide, available by selecting Start»Program Files»National
Instruments»<LabVIEW>»Module Documents»FPGA Interface User
Guide, for information about the FPGA Interface functions.