Summary: In this exercise, the objective is to build a VI that reads and writes information from the NI Instrument Simulator using VISA functions. Complete the following steps to build a VI that uses VISA calls to acquire data from the NI Instrument Simulator.
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Place the VISA Open
function, located on the Functions>>All
Functions>>Instrument I/O>>VISA>>VISA Advanced
palette, on the block diagram. This function opens a
VISA session with an instrument. Right-click the
VISA resource name input and select
Create>>Control from the shortcut menu.
VISA Write
function, located on the
Functions>>All Functions>>Instrument
I/O>>VISA palette, on the block
diagram. This function writes a string to the
instrument. Right-click the write buffer input and
select Create>>Control from the
shortcut menu.
VISA Read
function, located on the
Functions>>All Functions>>Instrument
I/O>>VISA palette, on the block
diagram. This function reads data from the
instrument. Right-click the byte count input and select
Create>>Control from the shortcut
menu. Right-click the read buffer output and select
Create>>Indicator from the shortcut
menu.
Place the VISA Close
function, located on the
Functions>>All Functions>>Instrument
I/O>>VISA>>VISA Advanced palette, on
the block diagram. This function closes the session with
the instrument and releases any system resources that
were used.
Place the Simple Error Handler
VI, located on the Functions>>All
Functions>>Time & Dialog palette, on
the block diagram. This VI checks error conditions and
opens a dialog box with error information if an error
occurs.
My VISA Write & Read.vi in the
C:\Exercises\LabVIEW Basics I directory.
devsim in the
VISA resource name input and set byte
count to 200 to make sure you read all the
information. Type *IDN? in the write
buffer and run the VI.
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