Dalsa PC2-CamLink, User Manual

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PC2-CamLink User's Manual Part I: PC2-CamLink Board
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User Timer
PC2-CamLink offers a user timer that can be used to fire a line acquisition at a specified frequency.
Note this user timer is asynchronous to all input pins.
The line rate generated by the user timer ranges from 1 μ s to 65535 μ s in steps of 1 μ s.
Virtual Frames Triggers
Virtual frame is a method grouping a number of consecutive lines from a linescan camera into a frame
buffer. This allows the application to manage host buffers using the same function calls independently
of the camera type (area or linescan).
Similar to area scan triggers, virtual frame triggers can use the opto-coupler trigger inputs, the LVDS
trigger inputs, or a SW trigger.
PC2-CamLink supports variable frame length, where a stop event indicates the end of the virtual frame
before the virtual frame buffer is filled. Note that if the stop event arrives after the virtual frame is
filled, this ‘late’ stop event will be discarded and the next virtual frame acquired during the next start
event. In variable frame length, the application specifies the largest virtual frame. This means that only
the first lines of the virtual frame buffer (up to the stop event) will be valid. Other lines will contain
the garbage that was already there before the start of acquisition.
See the following table for the virtual frame trigger sources: