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Features AW00123404000
226 Basler ace USB 3.0
8.6.4 Sequencer Operation
In this section, you will find a duplicate description of sequencer operation in sequencer mode:

a general overview employing a state diagram ( Figure 87 ), and

a more elaborate presentation of selected use cases ( Figure 88 through Figure 90 ).
As explained in Section 8.6.1 , there are a sequencer configuration mode for sequencer
configuration and the sequencer mode that allows to apply different sequencer sets in quick
succession to different frame acquisitions.
In the sequencer mode, one sequencer set after the other can be loaded into the active set
("sequencer set advance") as frames are acquired. The loading is controlled by using certain
sequencer trigger sources that can be selected for two schemes of sequencer set advance, called
paths. For more information about sequencer trigger sources, sequencer set advance, and paths,
see
Section 8.6.2.2 .
The actual sequence of sequencer sets that will be loaded into the active set as images are
acquired depends on the number of configured sequencer sets, on the use of the sequencer trigger
sources selected for path 0 and path 1, and on the use of the paths. For more information about
sequencer trigger sources and paths, see
Section 8.6.2.2 .
As mentioned in Section 8.6.2.2 , paths 0 and path 1 play different roles: The cycling through the
available sequencer sets can be accomplished using the path 1 sequencer trigger source. Using
the path 0 sequencer trigger source will load sequencer set 0 into the active set. This will reset the
cycling and allow its restart.
Note: You may occasionally encounter a transitional "dummy" sequencer set with index number -1.
Ignore this set. It occurs for technical reasons only and cannot be used for image acquisition.
To ensure reliable coordination between synchronous sequencer set advance and
frame start triggering, allow sufficient time to elapse between the moment when
the sequencer set advance trigger signal has reached the high status and the
subsequent frame start trigger signal going high.
In particular, consider the propagation delays associated with the camera’s input
lines: To minimize propagation delays, we recommend choosing the GPIO input
lines as the sources for both, the sequencer set advance trigger signal and the
frame start trigger signal. In this context, we recommend not using the opto-
isolated input line unless robustness against EMI is required.
You can achieve the tightest timing control if you set the frame start trigger signal
as the source for the sequencer set advance trigger signal.
We also recommend using the "fast" edges of the input lines.
For more information about propagation delays of the input lines, see Section 5.10
on
page 69 .