How do you manually UNT/UNL the GPIB from the non-controller side?

[David1 146]

Currently, my GPIB non-controller application stays in Listener mode after a read and Talker mode after a write; as a quick fix I have a short timeout period (30ms) before the non-controller checks the status of the bus, but I would like to return the non-controller to the "idle" state once it is finished talking or listening. (In my situation, I am not in charge of the controller and what GPIB program it is running.)

[rtamblin]

You will not be able to control what can Talk or Listen unless you do it from the Controller in Charge. From the CIC, the command for ibconfig would be ibcUnAddr, where the value following means:

zero = Do not send Untalk (UNT) and Unlisten (UNL) at the end of device-level reads and writes.

non-zero = Send UNT and UNL at the end of device-level reads and writes.
Default: zero.

Ryan Tamblin
Applications Engineer
National Instruments

[chris_amadasun]

Hello,
Can you give us a bit more information on what you are trying to accomplish with the UNL command?

Also can you try VISA interactive control and put in sequentially the commands being set by your LabVIEW application
and compare them with the NI Spy log of your LabVIEW application?

You might also take a look at this forum post.