Using A Software Trigger Signal - GigE VA Series User Manual

8.3.2

Using a Software Trigger Signal

If the Trigger Mode parameter is set to On and the Trigger Source parameter is set to Software, you must
apply a software trigger signal (exposure start) to the camera to begin each frame acquisition. Assuming that the
camera is in a waiting for exposure start trigger acquisition status, frame exposure will start when the software
trigger signal is received by the camera. Figure 8.2 illustrates frame acquisition with a software trigger signal.
When the camera receives a software trigger signal and begins exposure, it will exit the waiting for exposure
start trigger acquisition status because at that point, it cannot react to a new exposure start trigger signal.
As soon as the camera is capable of reacting to a new exposure start trigger signal, it will automatically return to
the waiting for exposure start trigger acquisition status.
When you are using a software trigger signal to start each frame acquisition, the camera's Exposure Mode
parameter must be set to Timed. The exposure time for each acquired frame will be determined by the value of
the camera's Exposure Time parameter.
When you use a software trigger signal to acquire frames, be aware that there is a Trigger
Latency due to the characteristics of the Gigabit Ethernet. Use an external trigger signal to
precisely synchronize the trigger signal with the exposure timing.
When you are using a software trigger signal to start each frame acquisition, the frame rate will be
determined by how often you apply a software trigger signal to the camera, and you should not attempt to
trigger frame acquisition at a rate that exceeds the maximum allowed for the current camera settings.
(There is a detailed explanation about the maximum allowed frame rate at the end of this chapter.)
Software trigger signals that are applied to the camera when it is not ready to receive them will be ignored.
Figure 8.2 Frame Acquisition with Software Trigger Signal
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