Command Reference 8-35
:FETCh :ARRay?
8 <fetch array size>|MAX *
Fetch an Array of Results
:FETCh:ARRay? query differs from the :FETCh? query by fetching several mea
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suring results at once.
An array of measurements must first be made by the commands. :INITiate,
:MEASure:ARRay? or :CONFigure:ARRay;:READ?
If the array size is set to a positive value, the first measurement made is the first
result to be fetched.
When the counter has made an array of measurements, :FETCh:ARRay? 8 10
fetches the first 10 measuring results from the output queue. The second
:FETCh:ARRay? 8 10 fetches the result 11 to 20, and so on. When the last mea
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suring result has been fetched, fetch:array starts over again with the first result.
In totalizing for instance, you may want to read the last measurement result instead
of the first one. This is possible if you set the array size to a negative number. Ex
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ample: :FETCh:ARRay? 8 –5 fetches the last five results. The output queue
pointer is not altered when the array size is negative. That is, the example above
always gives the last five results every time the command is sent.
:FETCh:ARRay? 8 –1 is useful to fetch intermediate results in free-running or ar-
ray measurements without interrupting the measurement.
Parameters
:ARRay means that an array of retrievals is made for each :FETCh command.
<fetch array size> is the number of retrievals in the array. This number must not
exceed the number of results in the measurement result buffer. The maximum limit
is 10000 due to the physical size of the output buffer.
* CNT-91 only: MAX means that all the results in the output buffer will be fetched.
Returned format: <data>[,<data>]¿
The format of the returned data is determined by the format commands :FORMat
and :FORMat:FIXed.
Example:
If :MEAS:ARR:FREQ? 8 (4) gives the results 1.1000,1.2000,1.3000,1.4000
:FETC:ARR 8 2 fetches the results 1.1000,1.2000
:FETC:ARR 8 2 once more fetches the results 1.3000,1.4000
:FETC:ARR 8 –1 always fetches the last result 1.4000
Val = measurement value (double precision in REAL and PACKed)
TS = timestamp value (double precision in REAL and int64 ps in PACKed)
If no valid result can be returned, e.g. due to time-out, the returned data will de
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pend on the chosen GPIB mode according to the table below.