Teledyne LeCroy TA660СА - Manual (Page 75)

TA660 User's Manual Catalyst Enterprises, Inc
69
Set Trigger
Set trigger is available to be set by the user for states S1 - S31. When
set trigger is selected, a trigger is enabled, when the Sequencer enters
that state for the first time. The amount of data to be captured before
and after the trigger may be set as a percentage of pre-trigger,
between 0% and 100%. This may be done by positioning the pre-
trigger slider to the desired percentage. This feature allows the
evaluation of bus activity leading up to and after the triggering event.
The operation of the pre trigger in the data memory is conceptually
illustrated in Figure 64
Pre-Trigger Data: The capture of the specified percentage of the data prior to
the triggering event cannot be guaranteed and may in some
cases be 0. This can occur in cases where the triggering
event occurs before the required number pre-trigger event
data can be stored. In these cases the data display will show
fewer than the specified data points prior to the triggering
event.
Figure 64 Pre-Trigger Example, 20% Pre-Trigger