Siemens SIMATIC MV500 Operating Manual page 33

Parameter Possible values
Edge-triggered
•
start/stop
•
Timeout 0.0 ... 600.0 s
Recognize double 0 ... 50
reads
Buffer deleted if
•
absent
•
Scan
With this setting, you can use the reader to scan a code on an object, for example, on a
rotating shaft. In contrast to the "Auto-trigger" option, a number of images can be buffered
and processed later. This may result in long processing times. Example: very poor marking.
One code is read per trigger signal. The code must be fully visible in one of the acquired
images. If a code cannot be decoded in any of the acquired images, an "N_OK" read is
output.
SIMATIC MV500
Operating Manual, 05/2019, C79000-G8976-C495-02
Default
Off
On
Off
5.0 s
1
Off
On
Off
Description
Only valid when the initial trigger is enabled and the trigger
source is DI/DO or PROFINET. The attempt to read is end-
ed either by a successful read or by a negative edge after
the timeout. If reading is aborted by a negative edge, the
"N_OK" result is output.
Valid only when initial trigger is enabled. The read attempt is
ended either by a successful read or at the latest after a
timeout. If reading is aborted due to a timeout, the "N_OK"
result is output. Setting 0.0 s only makes sense when "Edge
triggered start/stop" is enabled and reading needs to be
stopped immediately with a negative edge.
The result buffer is used to avoid multiple output of results.
0: Each read code is output (again) with each read.
•
1: If the content of the code that is currently in the image
•
matches the last code read, the code is not output
again. If the content of the code has changed, the next
output is made.
n: As 1, but the last n different code contents are stored
•
and compared before output.
Valid only when initial trigger is disabled. The buffer is de-
leted as soon as there is no readable code in the image. If
the code moved out of the image in the meantime, it is pos-
sible to read the same code multiple times using the "Auto
trigger" function.
Note
When an image acquisition interval that is too short is se-
lected, unintended double readings may occur.
Application
5.1 Program
33