Changing SCPI commands

[DanB83]

Hello,

I am currently using SCPI commands to control my instrument (Agilent 8714ES VNA), making use of the Instrument I/O Assistant in LV.

At the moment, I can tell my instrument to output a given power (say -30dBm) by entering the command "SOUR: POW:IMM:AMPL -30" into the ASCII representation window.

However, I would like to be able to tell it to output a certain power based on the result of a calculation done in LabVIEW.  Is there any way of feeding the Instrument I/O assistant with a 64-bit double "wire" to control a given instrument parameter?  Is there another way of doing this?

Thanks,

Dan

Message Edited by DanB83 on 10-23-2007 04:44 AM

[falkpl]

Use format to string with the string formater as "SOUR: POW:IMM:AMPL %d" and pass the dB as in int to the input terminal then pass this string to VISA write.  The visa write will also take a session and error io.

Paul 

[Dennis_Knutson]

With a current version of the Instrument I/O Assistant, you can add parameters to a write step. A dbl is one of the options.