Functions
Leuze electronic
DCR 248i
18
4.1.4
Presentation mode
In the "Presentation mode" camera operating mode, the code reader is in the idle state in a kind of wait
mode.
In the event of a change in the image area, e.g., by holding up a code, the code reader captures images
with illumination (as previously configured) until a code is read successfully. The code reader then switches
back to the wait mode and the illumination switches off after a few seconds.
Reading the same code multiple times
To prevent the same code from being read and output repeatedly in the "Presentation mode" camera oper-
ating mode, a delay time can be defined that must elapse before a code can be read again.
Configuration > Control > Reread delay
Sensitivity
This function can only be activated in the "Presentation mode" camera operating mode. You can set the
sensitivity threshold at which a change in the field of view is to be detected: 0 … 100.
• 0 = not sensitive
• 100 = sensitive
4.1.5
Continuous mode
In the "Continuous mode" camera operating mode, the code reader operates continuously in process
mode. In this mode, image acquisition is started again immediately after an image has been processed. An
external trigger signal is not required.
Image frequency
You can limit the maximum number of images per second. A reduction in image frequency is recom-
mended for slow applications where the object with the code moves slowly past the code reader. Consider
here the decoding time per decoding.
• It is recommended to limit the decoding time.
• It is recommended to deactivate the NO READ output.
4.2
Reference code comparison
With the reference code comparison, the code reader compares the actual decoding result with a stored
reference code – the exact code content is compared.
Options for teaching-in a new reference code:
• webConfig tool:
Configuration > Decoder > Reference
• Online command via the host interface
• Signal via a digital switching input
• TEACH function on the control panel of the code reader
In the webConfig tool, the exact code content can be entered for comparison.
Regular expressions
As an alternative to the exact code comparison, regular expressions can be used for a partial comparison.
Regular expressions can only be entered via the webConfig tool (see chapter 9 "Commissioning –
Leuze electronic webConfig tool").
Detailed information on regular expressions can be found on the Internet under Perl Compatible Regular
Expressions (PCRE)
http://www.pcre.org/
.
• Example 1
The code reader is to perform a partial comparison of two characters "42". Any number of characters
and content may precede the string "42".
• Comparison string entered in the webConfig tool: 42
• Positive reference code comparison (match): 123
42
5
• Negative reference code comparison (mismatch): 12345
