User`s guide

Easy Ways to Control Instruments Chapter 3
VEE User’s Guide 151
3 Select Flow ⇒ Repeat ⇒ For Range and place it to the left of
the Direct I/O object.
4 Connect the For Range data output pin to the Direct I/O data
input pin.
5 Edit the fields in For Range to: From 10, Thru 1.8M, and
Step 50k.
For Range will now send out numbers ranging from 10 to 1.8
million in steps of 50,000. As the numbers are received by the
Direct I/O object, the command string causes the function
generator to output the frequencies. The Direct I/O setup
should look like
Figure 95.
Figure 95 Direct I/O Setup Using an Input Variable
6 (Optional) Connect an HP3325B to your computer, if you
have one, and edit the configuration of this Direct I/O object
to include the address of the instrument. Run the program
and you will see the instrument generating these frequencies.
Reading Data From an Instrument
Instruments send data to a computer in many different formats.
To read data from an instrument, you must know the datatype
you want to read, and whether the data is returned as a single
value (scalar) or an array. You must also know if the instrument
returns data as text (ASCII) or binary.
You can find this information in the instrument documentation,
or you can use the VEE Bus I/O Monitor in the I/O menu to
examine the data being returned. This information determines
how to configure the I/O transaction.