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Xtium-CL PX4 Reference
Xtium-CL PX4 User's Manual
and should never occur.
The Sapera event value is CORACQ_VAL_EVENT_TYPE_DATA_OVERFLOW.
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Frame Valid
Event generated on detection of the start of a video frame by the board acquisition
hardware. Acquisition does not need to be active; therefore, this event can verify a valid
signal is connected. The Sapera event value is
CORACQ_VAL_EVENT_TYPE_VERTICAL_SYNC.
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Pixel Clock (Present/Absent)
Event generated on the transition from detecting or not detecting a pixel clock signal. The
Sapera event values are CORACQ_VAL_EVENT_TYPE_NO_PIXEL_CLK and
CORACQ_VAL_EVENT_TYPE_PIXEL_CLK.
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Frame Lost
The Frame Lost event indicates that an acquired image failed to transfer to on-board
memory. An example is if there are no free on-board buffers available for the new image.
This may be the case if the image transfer from onboard buffers to host PC memory is not
sustainable due to bus bandwidth issues or no host buffers are available to receive an
image.
The Sapera event value is CORACQ_VAL_EVENT_TYPE_FRAME_LOST.
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External Line Trigger Too Slow
Event which indicates that the detected shaft encoder input tick rate is too slow for the
device to take into account the specified shaft encoder multiplier value. The Sapera event
value is CORACQ_VAL_EVENT_TYPE_EXT_LINE_TRIGGER_TOO_SLOW.
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Shaft Encoder Reverse Count Overflow
Event which indicates that the shaft encoder has travelled in the opposite direction expected
and that the number of pulses encountered during that travel has exceeded the acquisition
device counter. The acquisition device will thus not be able to skip the appropriate number
of pulses when the expected direction is detected. The Sapera event value is
CORACQ_VAL_EVENT_TYPE_SHAFT_ENCODER_REVERSE_COUNT_OVERFLOW
Transfer Events
Transfer events are the ones related to the transfer module. Transfer events provide feedback on
image transfer from onboard memory frame buffers to PC memory frame buffers.
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Start of Frame
Start of Frame event generated when the first image pixel is transferred from on-board
memory into PC memory.
The Sapera event value is CORXFER_VAL_EVENT_TYPE_START_OF_FRAME.
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End of Frame
End of Frame event generated when the last image pixel is transferred from on-board
memory into PC memory.
The Sapera event value is CORXFER_VAL_EVENT_TYPE_END_OF_FRAME.
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End of Transfer
End of Transfer event generated at the completion of the last image transfer from on-board
memory into PC memory. Issue a stop command to the transfer module to complete a
transfer (if transfers are already in progress). If a frame transfer of a fixed number of
images is requested, the transfer module will stop transfer automatically. The Sapera event
value is CORXFER_VAL_EVENT_TYPE_END_OF_TRANSFER.
