Where is the function to address an instrument to talk?

[Julia2013]

Hi all, my question might look stupid, but I am curious

to figure out how labview does to control a instrument , in a systematic view!

I read the operational manual for HP8903B,  it says that it send the data message when addressed to talk,

So I believe we can only read the measurement result when this instrument is addressed to talk.

I downloaded the "hp8903b driver for Labview2012", and looked through some application examples.

and found the HP8903B Initialize.vi inside, where there is a VISA open function in it,

I read the file "visa.h", but did not find , how labview did to address an instrument to talk,

I think it has called some lower level functions,

where can I find them?

[GerdW]

Hi Julia,

you should read some manuals on basics of GPIB bus/connections!

The TALKER/MASTER thing is handled by some basic commands or even special lines on the connector. You don't need to worry about that! As you can see in your example driver all you need are GPIBWrite and GPIBRead commands (or VISAWrite/Read), all the rest is handled by the driver internally...

[JÞB]

With legacy equiment like this one you need to throw the dip switches on the back of the unit to select address and Talker/Listener options.