Crystal Instruments Coco-80 - Page 94

CoCo-80 User Manual
89
Trigger Condition
Illustration
Trigger Source > High Level
(rising edge)
High
threshold level
Trigger Source < Low Level
(falling edge)
Low
threshold level
Low Level < Trigger Source <
High Level (level trigger)
Low
threshold level
High
threshold level
(Trigger Source > High Level)
OR (Trigger Source < Low
Level) (edge trigger)
Low
threshold level
High
threshold level
Trigger Delay
Trigger delay allows a captured signal to include some data before or after the
trigger event. This is done by defining some number of points, or the percentage
of the total Block Size, that the capture occurs after the trigger event. For example,
if the Block Size is set to 1024 and the trigger delay is 10%, the data capture will
happen 102 points after the trigger event.
A negative trigger delay is more common for transient data capture. Negative
trigger delay means that the data capture will include data points before the
trigger event. For example, a -10% trigger delay means that the data capture will
include 102 data points before the trigger event with Block Size 1024. Some
instruments call a negative trigger delay a Pre-Trigger. The following picture
shows the concept of a negative trigger delay: