JAI CV-A11 User Manual
CV-A11
6.4. External Trigger Modes
This camera has 6 external asynchronous trigger modes, which can be set by RS-232C commands.
1.
Edge Pre-select Mode.TR=1
Pre-selected exposure. (SM=0, SM=1)
2.
Pulse Width Control Mode. TR=2
Pulse width controlled exposure. (HC=0, HC=1)
3.
Frame Delay read out mode. TR=3 PWC exposure read out by ext. VD. (HC=0, HC=1)
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
6.
Smearless Read out mode. TR=6
EPS Exp. after fast dump readout.(SM=0, SM=1)
The default accumulation is HD synchronously accumulation (HC=0). The accumulation starts at
the first HD after the trigger leading edge. Details are shown in fig.15.
In PWC mode (TR =2) and Frame Delay readout (TR=3), the accumulation mode HC can be set to
asynchronous accumulation (HC=1). The exposure will start immediately at the leading edge of
the trigger pulse without waiting for the HD. Fig. 16. below shows the details.
In Edge pre-select TR=1 and smearless TR=6, the shutter mode can be SM=0 or SM=1.
Smearless read out will reduce the smear caused by highlighted zones seen in images taken with
a short shutter speed. Before the accumulation can start, a fast dump read out is performed. It
takes 28H from trigger leading edge to start of accumulation.
Smearless read out will reduce the smear caused by highlighted zones seen in images taken with
a short shutter speed. Before the accumulation can start, a fast dump read out is performed. It
takes 28H from trigger leading edge to start of accumulation.
Important notes on using trigger modes
• The HD synchronized accumulation starts at the first HD after the trigger leading edge.
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 A, which is 8 µsec.
shown in fig. 14. The trigger level translations should be placed inside A, which is 8 µsec.
• Do not input a new trigger before the previous video is read out. (WEN is high).
Fig. 14. Trigger/HD timing.
A=8 µsec
t
1
t
2
t
3
t
4
t
5
HD
Trigger
Xsub
Xsg
EEN
Accum
t
1
t
2
t
3
t
4
t
5
HD
Trigger
Xsub
Xsg
EEN
Accum
HD
Trigger
Xsub
Xsg
EEN
Accum
Note:
Xsg and Xsub are
internal signals in the
camera. They are shown
in the timing diagram
for better
understanding.
internal signals in the
camera. They are shown
in the timing diagram
for better
understanding.
Fig. 15. Pulse Width H synchronous accumulation.
H D
T rigg er
X sub
X sg
E E N
A ccum
t
1
t
2
t
3
t
4
H D
T rigg er
X sub
X sg
E E N
A ccum
t
1
t
2
t
3
t
4
Fig. 16. Pulse Width H asynchronous accumulation.
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