Figure 4-3 Trigger Edge; External Trigger Edge - Microscan MS-3 User Manual

External Trigger Edge

Usage: This mode is highly recommended in any application where conveying
speed is constant or if spacing, object size, or timeouts are consistent.
Definition: External Trigger Edge, as with Level, allows the read cycle to begin
when a trigger (change of state) from an external sensing device is
received. However, the passing of an object out of sensor range does not
end the read cycle. The read cycle ends with a good read output or,
depending on End of Read Cycle setting, a timeout or new trigger
occurs.
Object
detector
Object
detector
Serial Cmd: <K200,3>
Important: Level and Edge apply to the active logic state (Positive or Negative)
that exists while the object is in a read cycle, between the rising edge and falling edge.
Rising edge is the trigger signal associated with the appearance of an object. Falling
edge is the trigger signal associated with the subsequent disappearance of the object.
Important: Level and Edge apply to the active logic state (Positive or Negative)
that exists while the object is in a read cycle, between the rising edge and falling edge.
Rising edge is the trigger signal associated with the appearance of an object. Falling
edge is the trigger signal associated with the subsequent disappearance of the object.
Initiate Read Cycle:
Object # 1, moving in front of the
1
detector beam, causes a change in
the trigger state, initiating the read
cycle.
Initiate Second Read Cycle:
Object # 2, moving in front of the
detector beam, causes another
change in the trigger state. This
2
signal initiates a new read cycle
and ends the previous read cycle
unless Timeout is enabled and a
good read or timeout has not
occurred.

Figure 4-3 Trigger Edge

Chapter 4 Read Cycle
Associated waveforms
assume External State
is set to Positive.
MS-3 Laser Scanner User's Manual
Active
0
Active
0
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