Agilent Technologies 8719ES, Programmer'S Manual

Page: 297 / 541

Chapter 2 2-5
Introduction to Instrument Control
Instrument Control using the VXIplug&play Driver
Verifying the Bus Connection
Check the interface bus connection and operation by following the appropriate procedure
(for the type of interface card you are using) below.
Interface Bus Verification Procedure (GPIB Interface Card)
1. Check the bus connection by running the VISA Assistant in the I/O Libraries. The VISA
Assistant will automatically report what it finds on the bus. Refer to Figure 2-1 . Notice
that the VISA Assistant is reporting instruments at addresses 16 and 17. As mentioned
earlier, these addresses designate the instrument and its display, respectively.
Figure 2-1 VISA Assistant Window
2. To further verify GPIB operation, send a preset command to the analyzer by doing the
following in the VISA Assistant window (refer to Figure 2-1 ):
a. Single-click on “GPIB0::16::INSTR” to highlight it.
b. Make sure that the “Formatted I/O” tab is selected.
c. Enter
PRES;
in the text box.
d. Click on “viPrintf.”
e. This command should preset the analyzer. If an instrument preset does not occur,
there is a problem. Check all GPIB address settings and physical connections. Most
GPIB problems are caused by an incorrect address or faulty/loose GPIB cables.