The purpose of this document is to summarize the supported trigger modes for the Allegro cameras. Trigger control is based on the GeniCam SFNC 2.3 specification which goes into more detail if needed.
When the sensors are capable, Triggers will start integration during data readout. Otherwise readout will need to complete before starting integration.
Relevant GeniCam Feature Registers
Continuous – This is the only SFNC supported mode at this time.
SingleFrame, MultiFrame – These are ISG specific modes and are not SFNC compatible at this time. These will be updated to SFNC compatibility in the near future or customer request.
AcquisitionStart - Starts the Acquisition of the device. The Acquisition might be conditioned by various triggers. An AcquisitionStart command must be sent to the device before the acquisition related triggers become effective.
AcquisitionStop - Stops the Acquisition of the device at the end of the current Frame.
TriggerMode - Controls if the selected trigger is active. Values are On and Off.
TriggerSelector - Selects the type of trigger to configure.
AcquisitionStart - Selects a trigger that starts the continuous Acquisition of frames.
FrameStart - Selects a trigger starting the capture of one frame.
FrameBurstStar -: Selects a trigger starting the capture of the bursts of frames in an acquisition. AcquisitionBurstFrameCount controls the length of each burst.
FrameBurstActive - Selects a trigger controlling the duration (active time of trigger based on pulse width) of the capture of the bursts of frames in an acquisition.
TriggerActivation - Specifies the activation mode of the trigger. Values are RisingEdge and FallingEdge.
TriggerSource - Specifies the internal signal or physical input Line to use as the trigger source.
TriggerSoftware - Generates an internal trigger. TriggerSource must be set to Software.
TriggerDelay – Specifies the delay in microseconds to apply after the trigger reception before activating it.
TriggerInterval – An ISG Custom register that specifies the time between the start of frames in useconds. The user should set this to be greater than the higher of either integration time or readout time.
ExposureMode – Values are Timed, TriggerWidth
Transfer Mode Summary
For the various transfer modes in the table below, the following are always set:
AcquisitionMode - Continuous
TriggerActivation - RisingEdge, FallingEdge
TriggerSource - Software (use TriggerSoftware to activate), Line0, Line1
TriggerDelay - Delay value (usec)TriggerInterval - Interval value for Burst Frames mode only (usec)
|On receiving AcquistionStart, frames are sent continuously until AcquistionStop.|
|Continuous Acquisition with AcquisitionStart trigger|
|On receiving AcquistionStart and after trigger, frames are sent continuously until AcquistionStop.|
|On receiving AcquistionStart, one frame is sent after each trigger.|
frames per trigger
|On receiving AcquistionStart, AcquisitionBurstFrameCount frames are sent after each trigger. TriggerInterval determines the time between the start of frames.|
|Variable Burst Frames|
|On receiving AcquistionStart, frames are sent continuously while trigger is in its active level.|
|On receiving AcquistionStart, one frame is sent after each trigger with Exposure determined by the trigger pulse width.|