Agilent Technologies 8960 Series Reference Manual page 150

Triggering of Measurements
Measurement States
The following examples describe states of the test set under various conditions. Refer to
149.
Example 17. Inactive State
If the test set has just been powered on, or any form of preset has been performed, then the measurement state
is inactive.
Example 18. Wait for Trigger State
If a measurement has been initiated with the INITiate command but has not been triggered, or a
measurement has been selected from the Measurement Selection menu but has not been triggered, then the
measurement state is wait for trigger.
Example 19. Measuring and Idle States (Trigger Arm Single)
If the trigger arm is set to single, the trigger source is available, and the trigger qualifier (optional) is satisfied,
the measurement state transitions to measuring and measurement results are now available to the user. The
state then transitions to idle (awaiting another INITiate).
Example 20. Measuring State (Trigger Arm Continuous)
If the trigger arm is set to continuous, the trigger source is available, and the trigger qualifier (optional) is
satisfied, the measurement state transitions to measuring and measurement results are now available to the
user. The measurement is continually triggered until the measurement is deactivated. Measurement results
are only available after the measurement completes and before it rearms. The measurement is deactivated
using the INITiate:<MEAS>:OFF. or Close Measurement.
Trigger Arm (Single or Continuous) Description
Trigger arm determines if a measurement will make one measurement then return to idle (single), or
automatically rearm on completion of a measurement and repeat the process (continuous).
NOTE When operating the test set remotely, the recommended setting for the trigger arm parameter is
single. This ensures proper operation of the INIT:DONE? query which is used to control the
retrieval of measurement results when measurements are initiated concurrently.
When a continuously armed measurement gets a result, it is available to any currently pending
(waiting, hanging) FETCh? query. Then another measurement cycle is started immediately. At
this point the results are no longer valid. The INIT:DONE? query is used to determine when
there is a completed measurement with valid results that can be fetched. If you look for a
continuously armed measurement with valid results that can be fetched using INIT:DONE? then
you are unlikely to get anything but WAIT. Each time the Test Set is queried, it is 99% likely to be
making another measurement. Even if it did return a measurement name, by the time the
control program determines which FETCh? query to send, it is too late to fetch the results and
the FETCh? query just hangs until the next measurement cycle is done, nullifying the efficiency
provided by the INIT:DONE? query.
Pressing the Start Single key on the front panel will cause all currently active measurements with trigger
arm set to single to arm and make the measurement.
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S:\Hp8960\E1963A WCDMA\3.2 release\Reference Guide\Chapters\wcdma_prog_trig.fm
Figure 12. on page