Transfer trace data from the intrument - Anritsu MS2721B Spectrum Master

[MMLab user]

HI all,

I would like to solicit some helpful hints from you.

I am trying to transfer trace data from an Anritsu MS2721B spectrum master using the TRACE command. I have configured the instrument to run in a continuous sweep mode.

Using the Visa Interactive Control I am sending the following viWrite command to the instrument ":TRACe?\n"

viRead returns some alphanumeric characters which unfortunately I have been unable to decipher. The returned information looks something like this:

#42204\xe0\xcd\xfe\xff\xac\xcc\xfe\xff\x18\xc9\xfe\xff\xe8\xc4\xfe\xff\x8c\xc8\xfe\xffD\xd1\xfe\xffd\xd5\xfe\xffL\xc9\xfe\xff\x94\xc4\xfe\xff\x9c\xca\xfe\xff\xd8\xc5\xfe\ ...

From the user's guide I am able to understand that the first #4 means that a 4-digit length info will follow. The 4-digit length info is the next 4 byte characters -- "2204", means that the actual data block 2204 bytes will follow. 

I would just like to know how to decipher the data block? I have tried the command several times but I keep getting the same ASCII header with the same the number of data bytes i.e. 2204 but different alphanumeric characters in the subsequent data block.

I have tried by sending different format commands to the instrument before sending the TRACe query command like :FORMat:DATA INTeger,32 or :FORMat:DATA REAL,32 with no success.

When I run the ":TRACe:PREamble?\n" the trace header information is returned without problems.

I will be grateful if I can get any helpful hints.

[ttsukasa]

Hello

I recommend that you read the manual of Anritsu MS2721B or contact Anritsu.
NI can help construct your serial communication, but it works well.
All you need as the next step is to understand the measured codes of Anritsu MS2721B.
NI does not know the way.
It should be on the manual, or ask it to Anritsu.
It is the best way so far.

Sincerely,

Tomohide Tsukasaki NIJ

[MMLab user]

Hi Tomohide Tsukasaki san,
Thank you very much for your helpful suggestion.
I did manage to read the trace data from the instrument. Unfortunately, I was not giving enough time between the write command sent to the instrument and reading the data from the instrument. I discovered that the sweep takes several tens of seconds to finish. If I wait for about 50 ~ 60 seconds between the write and read command, I get the correct trace data.
Thank you all and sorry for any inconveniences caused.

[paolitz]

Hi :

Where can i get the library visa ?? i want to make a serial port code for an spectrum analyser anritsu.

Thanks,

Paola

paolitz@gmail.com