HP 1660CS, User Manual

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the oscilloscope is armed by an analyzer, the oscilloscope can only be armed
by the same analyzer that arms Port Out.
Acquisition Control field
Selecting the Acquisition Control field pops up the Acquisition Control menu.
The Acquisition Control menu sets the acquisition mode, the trigger position
within acquisition memory, and the sample period.
Acquisition Mode field
The Acquisition Mode field toggles between Manual and Automatic. When set
to Automatic, the sample rate and the position of stored data relative to
trigger are based on the sec/Div and delay settings in the Waveform menu.
When Acquisition Mode is set to Manual, additional configuration fields
become available. The additional configuration fields work together with the
sequence instructions in a prioritized manner to position the memory relative
to the trigger point. A small picture at the bottom of the menu displays the
sum effect of all the settings on the trigger position within memory.
Trigger Position field
The Trigger Position field sets how much information is stored before and
after the trigger. When a run is started, a timing analyzer will not look for a
trigger until at least the proper percent of pre-trigger data has been stored.
A state analyzer will trigger at the first occurrence of the trigger, but will
notify you that the prestore was not completed. After a trigger has been
detected, the rest of memory is filled before the analyzer halts.
In a timing analyzer, even when the trigger position is set to Start or End,
there will always be a small portion of pre-trigger and post-trigger data
stored. Most of the choices designate prestore and poststore percentages,
but the Delay setting affects when the memory begins storing data relative to
the trigger.
Delay The Delay field delays the start of acquisition storage after the
trigger. The delay time range is affected by the sample period but could
range from 16 ns to 8 ks. As the picture in the pop-up menu shows, any
data falling between the trigger and the delay time is not stored.
The Analyzer Trigger Menu
Acquisition Control field
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