ADLINK Technology cPCI-8168, User Manual

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76 Operation Theory
4.6.4 Trigger comparator
The trigger comparator is much like the general comparator only
with the ability to generate a trigger pulse when the condition is
met. Once the condition is met, the CMP pin on the connector will
output a pulse for a specific purpose, like triggering a camera to
catch a picture. Not all axes have this function only those with a
CMP pin. The following diagram shows the application of trigger-
ing.
In this application, the table is controlled by the motion command,
and the CCD Camera is controlled by the CMP pin. When the
comparing position is reached, the pulse will be outputted and the
image is captured. This is an on-the-fly image capture. If users
want to get more images during the motion path, try to set a new
comparing point right after the previous image is captured. This
method allows continuous image capturing.