Guidelines For Overlapped Operation; Illegal Line Acquisition By Overtriggering - Basler Racer User Manual

AW00118508000
6.2.1

Guidelines for Overlapped Operation

To ensure smooth line acquisition and avoid overtriggering, you may only apply a line acquisition-
related trigger when the camera is waiting for it. If the trigger is nonetheless applied, the trigger will
be ignored and considered an overtrigger.
The risk of overtriggering exists particularly for overlapped operation where the sequence of line
start triggers must be carefully coordinated both with the camera's exposure time and the sensor
readout time.
The following examples use a non-inverted, rising edge hardware line start trigger signal
(ExLSTrig).
6.2.1.1

Illegal Line Acquisition by Overtriggering

Certain attempts of triggering overlapped line acquisition are illegal and do not result in line
acquisitions: When a line start trigger signal attempts an illegal line acquisition the trigger signal will
be ignored and, accordingly, no line acquisition will be performed. In addition, the trigger signal will
be reported as an overtrigger (see also Section 8.10.2 on
impossible overlaps are shown in Fig. 23 on
Illegal triggering when overlapping line acquisitions:
The line start trigger goes high to start the exposure for line acquisition N+1 before the

exposure or the exposure overhead for line acquisition N has ended (see Fig. 23 on
This would result in the illegal overlap of exposures or of exposure and exposure overhead.
The exposure overhead (see Fig. 23 on
process. For simplicity, it is omitted from the other figures illustrating exposure
and readout (see, for example, Fig. 24 on
The duration of the exposure overhead is expressed by constant C
Section 6.2.1.2 on
The line start trigger goes low to end the exposure for line acquisition N+1 before readout for

acquisition N has ended (premature exposure end; see Fig. 24 on
This would result in the illegal overlap of two readouts (in trigger width exposure mode only).
Basler racer Camera Link
page
page 74 and Fig. 24 on
page
page 75 and Section 6.4.1 on
Acquisition Control
135). Illegal triggering and
page 74.
74) is part of every exposure
page 74).
page 89).
page 74).
page 74).
(see also
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