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6.3.6 Timings of the image transmission
6.3.6.1 VCXG
Trigger Mode
The transfer of the rst image starts after data for a complete packet size is stored in
camera's TX memory. All further images start the transfer immediately after the rst one
is completed, if the camera works in burst mode with a high frame rate and the sensor
acquires images faster than the interface can transfer. These additional pictures are not
referenced to the time of the readout. If the sensor is triggered slowly enough, each image
will behave like the rst image.
Freerun Mode
The transfer of each image starts after data for a complete packet size is stored in the
camera's TX memory. Since the sensor delivers more data than the interface can man-
age, depending on set ROI, images are repeatedly discarded and not transferred. There-
fore, gaps of different sizes can be created via the GigE interface.
6.3.6.2 VCXU
Trigger Mode
All images are written from sensor into memory as long as free buffers are available. If
this burst memory is full, all following images are discarded by the sensor. The transfer of
the rst image starts with a small delay (about 2 lines). The data is read from the memory
and transferred to the interface. The interface can now control reading from memory. De-
pending on the USB conguration (ThroughputLimit, blank packages), the interface can
retrieve the data quickly enough or is lagging.
Freerun Mode
Only one alternating buffer is provided in the memory. The rst image is written into the
memory and immediately transferred to the interface with a small delay. The second im-
age from the sensor is written into another buffer, which would be transferred immediately
afterwards. If the interface is too slow due to the current conguration and the rst image
has not yet been transferred completely when the third image is already received from
the sensor, the third image would overwrite the second one and would be transferred via
the interface next.
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