Chapter 4
Installing and Using the FieldPoint Software
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Using the FieldPoint LabWindows/CVI Functions
When you install the FieldPoint software, a LabWindows/CVI instrument
driver for FieldPoint is created if LabWindows/CVI has already been
installed on your computer. This instrument driver includes function panels
to call C functions that directly access the I/O Items you configured in the
FieldPoint Explorer program. In addition, a set of sample projects is placed
in your
LabWindows/CVI Samples
directory. These examples are the
best way to get familiar with these functions. The FieldPoint CVI Help
document is in the same program group on your Windows taskbar as the
FieldPoint Explorer program. This help document describes each function
in the instrument driver with a description of the C syntax, a description of
each parameter, and a list of possible error codes.
Note
FieldPoint CVI Interface Compatibility Modes: The FieldPoint software ships
with object (
.obj
) files to support the different compiler compatibility modes that
LabWindows/CVI supports (Microsoft Visual C/C++, Borland, Watcom, and Symantec).
When FieldPoint software is installed, the Microsoft compatibility mode is installed by
default. To use an alternate compatibility, copy the supplied
.obj
file from the compiler
folder (for instance,
/CVI/FieldPoint/borland/FieldPoint.obj
) with which you
would like compatibility to the
/FieldPoint
subdirectory of the CVI directory.
Using the FieldPoint OPC Server
OPC (OLE for Process Control) is an industry standard device interface
specification that provides interoperability between field devices such as
FieldPoint and application software packages. The FieldPoint OPC server,
like the other FieldPoint interfaces, imports the I/O Items that you
configured in FieldPoint Explorer and makes them available as OPC Items
to an
OPC client
, a software program designed to communicate with OPC
servers. The FieldPoint OPC server allows any application written as an
OPC client to access the FieldPoint hardware over the serial port. Because
OPC is based in part on Microsoft’s DCOM (Distributed Component
Object Model), it is even possible for an OPC client on one computer to
access FieldPoint hardware connected to the serial port of another
computer if the two computers are networked together.
OPC clients might differ in the features they offer and their presentation
of the OPC interface for the FieldPoint OPC server. Refer to the
documentation on using the OPC client features of your application for
detailed instructions on how to access an OPC server. However, the basics
steps involved are similar for most OPC client applications.
