DAP Technology 1394, Operation Manual

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Filter/Trigger
225 Copyright © DapTechnology B.V., 2005-2019 - All Rights Reserved., 5/20/2019
Trigger Position
In this box you can specify the trigger position in the Recorder memory and you can enable a cyclic buffer
for the data before the trigger.
Stop recording when buffer full
Selecting this option (default) will cause the Recorder to stop when the Recorder buffer is completely
filled. The Recorder will also stop when the data after the trigger reached the the amount indicated by the
Max post-trigger size slider.
Cyclic pre-trigger buffer
Selecting this option will enable a cyclic buffer for the data recorded before the Recorder has been
triggered. The size of this cyclic pre-trigger buffer is indicated by the Max pre-trigger size slider. If the
recorded data reaches the amount indicated by this slider, the oldest data in the pre-trigger buffer will be
overwritten by the new data.
Before the Recorder is triggered, the total used Recorder memory will never be more than indicated by
the Max pre-trigger size slider. As soon as the Recorder is triggered, the data in the pre-trigger buffer will
not be overwritten anymore and the remaining Recorder memory will be filled. The Recorder will stop
when the complete Recorder memory has been filled or when the data after the trigger reached the the
amount indicated by the Max post-trigger size slider.
Max pre-trigger size
This slider is only enabled when the cyclic pre-trigger buffer option is enabled. With this slider you can
specify the size of this pre-trigger buffer expressed in % of the whole Recorder memory. You can also
type a value in the text box at the right from the slider.
Max post-trigger size
With this slider you can specify the amount of Recorder memory to be used maximal for data after the
Recorder has been triggered. If this amount have been reached, the Recorder will be stopped. Note that
the Recorder will also stop when the complete buffer has been filled. You can also type a value in the text
box at the right from the slider.
Cyclic Buffer sizes Example
Suppose you have some bug, on which you could trigger, and after a while the communication stalls. So
you would like to trigger and record all data until no packets are present anymore. Suppose you want a
minimum of 50% pre-trigger data, but more if possible. And you want as much as pre-trigger data as
possible. Then you can put the pre-trigger at maximum, and the post-trigger to 50%.
By doing so, you'll get as much pre-trigger as possible and the amount of post-trigger depends on the
amount of post-trigger data present, but will never be more than 50%.
12.2.4. Filter
The Filter Tab is not available on
· Stealth Series in Symbol Recorder mode
Actual available options for filtering depend on the specific analyzer model used.
An example of the Filter page is shown below. It has a number of boxes to select the packet and or event
that you want to skip. The skipped packets are not stored in the Recorder memory.
It exists of the following boxes:
· 'Skip by packet type' box
· 'Skip by packet Set(s)' box
·
'Skip by speed' box
· 'Skip prefix-only packets' box
· 'Skip events' box