CV-A50 / CV-A60
6.4. External Trigger Modes
This camera has 5 external asynchronous trigger modes, which can be set by
1. | Edge | |
2. | Pulse Width Control Mode. TR=2 | Pulse width controlled exposure. |
3. | Frame Delay read out mode. TR=3 | PWC exposure read out by ext. VD. |
4.Long Time Exposure Mode. TR=4 Exposure is interval between ext. VD.
5. | Start/stop Mode. TR=5 | Exposure start by trigger and stop by ext. VD |
An external trigger pulse initiates the capture (input on pin 11 of the
The duration of the external trigger pulse must be greater than 1H. It is recommended to make this longer, typically 9H.
Important notes on using trigger modes:-
The accumulation is HD synchronously accumulation. The accumulation starts at the first HD after the trigger leading edge. Shown in fig. 15. To avoid the <1H jitter caused by this delay, synchronize the external trigger to HD as shown in fig. 14. The trigger level translations should be placed inside the time A, which is 8 µseconds.
Do not input a new trigger before the previous video is read out. (WEN is high).
A==88µsecµ ec
HD
Trigger
Accum
Xsub
Xsg
EEN
Fig. 14. Trigger/HD timing.
t1 | t2 | t3 | t4 | t5 |
Note: Xsg and Xsub are internal signals in the camera. They are shown in the timing diagram for better understanding.
Fig. 15. Pulse Width H synchronous accumulation.
Fig. 16. Ext. HD and ext. VD phase conditions.
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