Keithley 2750, Руководство пользователя

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Model 2750 Multimeter/Switch System User’s Manual Basic DMM Operation 3-51
[:SENSe[1]]:DATA:FRESh?
What it does
This query is similar to :FETCh? in that it returns the latest reading from the instrument
but has the advantage of making sure that it does not return the same reading twice.
Limitations
Like the :FETCh? query, this command does not trigger a reading.
When appropriate
This is a much better choice than the :FETCh? query because it can not return the same
reading twice. This would be a good query to use when triggering by BUS or EXTER-
NAL, because it will wait for a reading to complete if a reading is in progress.
The :CALC:DATA:FRESh? query is similar to the :DATA:FRESh? query but applies to
readings that have math applied to them (e.g., :MX+B scaling).
[:SENSe[1]]:DATA[:LATest]?
What it does
This query will return the last reading the instrument had, regardless of what may have
invalidated that reading, such as changing ranges or functions.
Limitations
This query is fully capable of returning meaningless, old data.
When appropriate
If, for some reason, the user wants the last completed reading, even after changing ranges
or other measurement settings, would invalidate the old reading.
The :CALC:DATA:LATest? query that is similar to the :DATA:LAT? query but applies to
readings that have math applied to them (e.g., : MX+B scaling).
2750-900-01.book Page 51 Wednesday, August 3, 2011 7:56 AM