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Operational Reference
Nano Series GigE Vision Camera
Trigger Mode Details
Genie Nano image exposures are initiated by an event. The trigger event is either the camera's
programmable internal clock used in free running mode, an external input used for synchronizing
exposures to external triggers, or a programmed function call message by the controlling
computer. These triggering modes are described below.
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Free running (Trigger Mode=Off): The Nano free-running mode has programmable internal
timers for frame rate and exposure period. Frame rate minimums, maximums, and increments
supported are sensor specific. Maximum frame rates are dependent on the required exposure.
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External trigger (Trigger Mode=On): Exposures are controlled by an external trigger signal
where the specific input line is selected by the Trigger Source feature. External signals are
isolated by an opto-coupler input with a time programmable debounce circuit.
Trigger Source Types (Trigger Mode=On)
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Trigger Source=Software: An exposure trigger is sent as a control command via the
Ethernet network connection. Software triggers cannot be considered time accurate due to
network latency and sequential command jitter. But a software trigger is more responsive than
calling a single-frame acquisition since the latter must validate the acquisition parameters and
modify on-board buffer allocation if the buffer size has changed since the last acquisition.
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Trigger Source = Line 1 or 2: An external trigger signal is opto-coupled and subject to a
signal debounce, input delay, plus inversion circuits.
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Trigger Line Polarity: For external line signals, a rising edge signal is suggested to minimize
the time it takes for the opto-coupler to change state.
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Trigger Source=Timer1End Event: The Timer1 End Event is used as the internal trigger
source. Refer to
Counter and Timer Controls
for information on those features.
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Trigger Source=Counter1End Event: The Counter1 End Event is used as the internal trigger
source.
Input Line Details
The general purpose input line signals are connected to I/O lines 1 and 2, which have the following
features for control or status indication.
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Feature set: LineSelector (RW), LineName (RO), linePinAssociation (RO), LineFormat (RO),
LineMode (RO), lineDetectionLevel (RW), lineDebouncingPeriod (RW), LineInverter (RW),
LineStatus (RO).
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Connector: See 10-pin I/O Connector Details for connector pinout and electrical information.
The cable shell and shield should electrically connect the Genie Nano chassis to computer
chassis for maximum EMI protection.
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Line Transition Validation: Each input incorporates a signal debounce circuit (following the
opto-couple) to eliminate short noise transitions that could be wrongly interpreted as a valid
pulse. The duration is user-programmable from 0µs to 255µs with CamExpert.
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Line Signal Propagation & Timing: Maximum delay values are defined in Input Signals
Electrical Specifications.
