JAI CV-A11 - Manual (Page 14)

CV-A11
6.9. Start/Stop Mode
The exposure time is controlled by the interval between the ext. trigger and the ext. VD signal.
The exposure starts at the first HD pulse after the falling edge of the ext. trigger, and stops at
the rising edge of the VD pulse. The range can be between 1/30 to 1/10,000 second. The
Start/Stop mode is a continuous mode where the VD signal must be given continuously. It is not
possible to input external VD randomly.
To use this mode:
Set function:
Trigger mode to “Start/Stop” TR=5
Polarity and other functions
Input: Ext. trigger to pin 5 on 6 pin connector (or 11 on 12 pin connector)
Ext. VD to pin 7 on 12 pin connector.
Ext. HD to pin 6 on 12 pin connector. (If used).
Fig. 21. Start/stop mode.
Important notes on using this mode: -
•
•
•
•
•
As the start of exposure will be synchronized with the internal H signal, the start of exposure
may be shifted by max 1H. To avoid this shift (jitter), synchronize the camera with an
external HD and make sure that the trigger pulse aligns to the HD signal as shown in Fig. 14.
Remark that the trigger should be applied up to 15.5 H after the ext. VD for the shortest
exposure.
External sync system should follow the camera scanning system.
See fig. 11 for the relationship between ext. HD and ext. VD.
Do not input a new trigger before the previous video is read out. (WEN is high).
- 13 -