Agilent Technologies E4406A VSA manual Improving the Speed of Your Measurements

Programming Fundamentals

Improving the Speed of Your Measurements

Improving the Speed of Your Measurements

There are a number of things you can do in your programs to make them run faster:

“Turn off the display updates.” on page 67.

“Use binary data format instead of ASCII.” on page 67.

“Minimize the number of GPIB transactions.” on page 68.

“Avoid unnecessary use of *RST.” on page 70.

“Minimize DUT/instrument setup changes.” on page 70.

“Consider using LAN instead of GPIB.” on page 70.

“Avoid automatic attenuator setting.” on page 70.

“Optimize your GSM output RF spectrum switching measurement.” on page 71.

“Avoid using RFBurst trigger for single burst signals.” on page 71.

“When making power measurements on multiple bursts or slots, use CALCulate:DATA[n]:COMPress?” on page 72.

Turn off the display updates.

:DISPlay:ENABle OFF turns off the display. That is, the data may still be visible, but it will no longer be updated. Updating the display slows down the measurement. For remote testing, since the computer is processing the data rather than a person, there is no need to display the data on the analyzer screen.

Use binary data format instead of ASCII.

The ASCII data format is the instrument default since it is easier for people to understand and is required by SCPI for *RST. However, data input/output is faster using the binary formats.

:FORMat:DATA REAL,64 selects the 64-bit binary data format for all your numerical data queries. You may need to swap the byte order if you are using a PC rather than UNIX. NORMal is the default byte order. Use :FORMat:BORDer SWAP to change the byte order so that the least significant byte is sent first. (Real,32 which is smaller and somewhat faster, should only be used if you don’t need full resolution for your data. You probably need full resolution if you have frequency data.)

When using the binary format, data is sent in a block of bytes with an ASCII header. A data query would return the block of data in the following format: #DNNN<nnn binary data bytes>

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