Omega Vehicle Security 1400 User Manual
Configuration Aspects for Programmers
Appendix B
B-20
ChartScan User’s Manual
Multiple Trigger Blocks
Through the Auto-Rearm capability of ChartScan, it is possible to capture more than one trigger block in the
unit’s Acquisition Buffer. Each trigger block would contain one and only one trigger point.
These trigger blocks are stacked end-to-end in the buffer; as the last reading of the first trigger block is read by
the controller, the next scan to be read will be from the second trigger block. The trigger can only be re-armed
after a trigger block has been completed. If the Auto-Rearm feature is not in use, a T command must be issued
to re-arm ChartScan for acquisition.
unit’s Acquisition Buffer. Each trigger block would contain one and only one trigger point.
These trigger blocks are stacked end-to-end in the buffer; as the last reading of the first trigger block is read by
the controller, the next scan to be read will be from the second trigger block. The trigger can only be re-armed
after a trigger block has been completed. If the Auto-Rearm feature is not in use, a T command must be issued
to re-arm ChartScan for acquisition.
It is important to note Auto-Rearm does not allow the user to change the configuration while armed. To stop
Auto-Rearm, the user must issue a
Auto-Rearm, the user must issue a
T
command with the flag set to zero.
If Auto-Rearm is selected, another acquisition will take place on the next trigger without any controller
intervention. This allows ChartScan to store several acquisitions contiguously in its internal memory. The
buffer locations of the trigger points and their associated time tags can be found in the Buffer Status String. The
read pointer is always on the oldest unread trigger block, so requests for pointer status will always correspond to
the trigger block available to be read. The next trigger, however, must be initiated AFTER the previous
acquisition was completed. Otherwise, a trigger overrun will occur.
intervention. This allows ChartScan to store several acquisitions contiguously in its internal memory. The
buffer locations of the trigger points and their associated time tags can be found in the Buffer Status String. The
read pointer is always on the oldest unread trigger block, so requests for pointer status will always correspond to
the trigger block available to be read. The next trigger, however, must be initiated AFTER the previous
acquisition was completed. Otherwise, a trigger overrun will occur.
Additional information about triggering and trigger error conditions can be found in the sections “Trigger
Latency” and “Trigger Overrun” later in this appendix.
Latency” and “Trigger Overrun” later in this appendix.