Chapter 3 Developing Your NI-488.2 Application
© National Instruments Corporation 3-9 NI-488.2 User Manual for Windows
GPIB address of your GPIB device, as described in Step 2. Determine
the GPIB Address of Your Device in the section Applications That Use
Multiple Interfaces or Communicate with Multiple GPIB Devices later
in this chapter).
•Secondary address for the GPIB instrument (0 if the GPIB instrument
does not use secondary addressing).
•Timeout period (typically set to T10s, which is 10 seconds).
•End-of-transfer mode (typically set to 1 so that EOI is asserted with the
last byte of writes).
•EOS detection mode (typically 0 if the GPIB instrument does not use
EOS characters).
A successful ibdev call returns a device handle, ud, that is used for all
device-level traditional NI-488.2 calls that communicate with the GPIB
instrument.
Step 2. Clear the Device
Use ibclr to clear the device. This resets the device’s internal functions to
the default state.
Device CommunicationStep 3. Communicate with the Device
Communicate with the device by sending it the "*IDN?" query and then
reading back the response. Many devices respond to this query by returning
a description of the device. Refer to the documentation that came with your
GPIB device to see specific instructions on the proper way to communicate
with it.
Step 3a.
Use ibwrt to send the "*IDN?" query command to the device.
Step 3b.
Use ibrd to read the response from the device.
Continue communicating with the GPIB device until you are finished.
CleanupStep 4. Place the Device Offline before Exiting Your Application
Use ibonl to put the device handle offline before you exit the application.