JAI CV-A11 Manuale Utente

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CV-A11
 
6.5. Edge Pre-select Mode 
An external trigger pulse initiates the capture (input on pin 11 of the 12-pin Hirose connector or 
pin 5 of the 6-pin Hirose). The leading edge of the trigger pulse initiates the exposure (this is a 
falling edge if factory default). If the polarity of this pulse is reversed, the camera can be 
configured to correct for it. The exposure time (accumulation time) is governed by the pre-
defined shutter speed set by RS-232C. 
 
To use this mode: 
Set function: 
Trigger mode “Edge Pre-select” 
TR=1 
 
 
 
 
Shutter mode to “Normal” or “Programmable” 
SM=0, SM=1 
  
 
 
 
Shutter Speed using fixed steps 
SH=0 through 7 
 
 
 
 
or Programmable exposure 
PE=1 through 1023 
 
 
 
 
Polarity and other functions 
 
Input:   
 
Ext. trigger to pin 5 on 6 pin connector (or 11 on 12 pin connector) 
 
 
 
 
Ext. HD to pin 6 on 12 pin connector. (If used).  
 
 
 
Fig. 17. Edge pre-select 
 
Important notes on using this mode:
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•  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. 
•  The duration of the external trigger pulse must be greater than 1H. It is recommended to 
make this longer, typically 9H. This is a TTL level pulse, which can be positive or 
negative going (the camera can be set to accept any polarity). 
•  Do not input ext. VD signal at pin 7 on 12 pin connector, as it may disturb the external 
trigger function. 
•  Do not input a new trigger before the previous video is read out. (WEN is high). 
 
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