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Logic Analyzer Reference
The Analyzer Trigger Menu
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 position of stored data relative to trigger
and the sample rate 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.

Memory Length

The Memory Length field set the amount of memory to be used for
acquisition. It applies to all acquisition modes. Only discrete sizes are
available (see “To set the memory length” on page 91). If you enter a
number with the keyboard, it is rounded to the nearest available
discrete size.

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.