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112 Appendix B: Camera interface reference
Variable line scan rate mode with variable frame size
In a variable line scan mode with variable frame size, the line rate is controlled by
an external line trigger frequency. The number of lines per frame is variable and
controlled by the frame trigger signal.
The frame grabber captures lines during the high level of the frame trigger. The
maximum number of lines captured can be changed by changing the active vertical
Y timing period in the DCF file. The line capture starts with the rising edge of the
frame trigger signal and ends with the falling edge.
R The following illustrates the timings for variable line scan mode with variable
frame size:
IMINA2005 frame trigger
L Y line trigger
camera
video signal1
exposure timer
video valid
pixel clock*
frame grabber
external frame trigger
variable2
RE MA exposure timer
exposure time
line valid
P 9 * optional signal
1 1. analog or digital
video
valid
video
valid
video
valid
2. the number of lines
captured during high level
