User Manual

6–6 Configuration: Symbology
Publication 2755-833
Code 128
Field Type Options
Select
No
Yes
Enables/disables decoding of Code 128 labels. The default of No
disables decoding of this symbology. Select Yes to enable decoding.
Code 128 Specific Lengths
Field Type Options
Edit Numeric 0 through 64 (0)
Sets length checking for Code 128 labels. The default is 0, which
means the decoder does not check lengths.
You can specify up to 8 code lengths (maximum of 64 characters).
The code length does not include the check character or the start
and stop characters.
①
If you specify a code length other than 0, the
decoder will only decode labels with the number of characters
specified.
The decoder uses the specific length parameter in three ways:
• The decoder discards decoded symbols with lengths that do not
match the specific length parameter
This allows you to filter out all decoded symbols except those
that have a specific length that appears in the specific length
table.
• The decoder uses it to determine if the number of bar to space
transitions that occur during a scan is appropriate for the
symbologies and specific length values
Scans that occur in the absence of a symbol or part of a symbol
are not valid, and therefore result in extra processing overhead for
the decoder. The decoder discards these scans before the
microprocessor sees them.
• Once the microprocessor sees a scan, it uses the specific length
parameter to search within the symbol for a valid number of bar
to space transitions
① The
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no
re C
od
e 128 FNC2
,
FNC3
,
and
FNC4
c
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dl
ess
o
f
t
he C
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e 128 FN
Character setting. FNC2, FNC3, and FNC4 are also ignored by the specific length parameter.