Passing control to an instrument over GPIB

[amaglio]

I am having trouble with passing control to an instrument on the GPIB bus. After communicating with instruments, the computer is then the CIC (controller in charge). Once I kick off a routine on one of the instruments it wants to be the CIC so it can communicate with a signal generator that is attached to it. Does anyone know how to pass control to an instrument? I am assuming I need to use the LabVIEW function "VISA GPIB Pass Control" but don't really know how to do this. What do i put for the VISA resource name in this case? For the primary address to i just put the number of the GPIB address of the instrument? Thanks for your help.

[Ryan_T]

Hi amaglio,

In order to pass contorl to an instrument on the GPIB bus you can use one of two functions in LabVIEW.  If you are currently using VISA functions then you should use the VISA GPIB Pass Control Function.  In this case, you will want to pass the existing VISA reference into the reference input or create a constant from the the input and select the correct GPIB interface.  If you are using the 488.2 functions then you should use the PassControl Function.  In either situation you will want to match the primary address to the instruments address which can be found in Measurement and Automation Explorer (MAX) after you queery for instruments. 

Thanks

[amaglio]

Thanks for your help Ryan... Once I pass control to the instrument, can I still communicate with it? Or once control is passed do I need to have some kind of script (BASIC code or something of this nature) loaded in the instrument ready to run. Basically, I want to pass control to the instrument, then initiate a measurement, and then once the measurement is done I need some way for the instrument to return control to the computer. Is there a way to do what I need to do without having to load a program into the instrument?

[Ryan_T]

Hi amaglio,

The Passing GPIB Control - System Controller vs. Controller In Charge Knowledge Base should help with your questions.

Thanks