Acquisition Mode Field
The Acquisition Mode field toggles between Automatic and Manual. When set
to Automatic in a state analyzer, the trigger position is computed based on
the sequence specification. In a timing analyzer, the trigger position and
sample period are computed based on the sec/Div and delay settings in the
Waveform menu.
When the Acquisition Mode field is set to Manual, additional configuration
fields become available. Use these fields to further qualify what data is
stored. The additional configuration fields work together with the sequence
instructions, in a prioritized manner, to position the trigger point relative to
the beginning and end of stored data.
Trigger Position Field
In a state analyzer, the trigger point position is determined after the
sequence instructions are evaluated. This process could result in a varying
portion of available memory being filled with post-trigger data. The
remainder of memory is considered free and is filled with less significant
data.
In a timing analyzer, after the specified trigger term is found, memory is filled
with post-trigger data starting at the trigger position represented by a blue
graphic bar with the "Trig" indicator line. If the trigger position is set to store
pre-trigger data, any true sequence instruction or trigger seen is ignored until
the proper amount of pre-trigger data has been stored.
The Trigger Position field accesses a selection of options:
•
Start
•
Center
•
End
•
User Defined
•
Delay
Start
When the trigger position is set to Start, it places the trigger near the
beginning of memory and most of the data in memory is post-trigger data.
The Trigger Menu
Acquisition Control Field
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