Datalogic DX8210, Reference Manual

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User Interface
94 DX8210 Barcode Scanner
This filter is based upon the following rules:
a multiple read condition occurs
all decoded codes of the same type are compared with each other
Rule 1: the shorter code is considered contained in the longer code if the character
string is found in the same order; the longer code may have a single block of
characters in any position (before, after or in between the compared strings)
Example: The code 123456 is considered contained in the following codes:
00123456, 12345600, 12378456.
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The code 123456 is not considered contained in the following codes: 12346507
(string out of order), 12345700 (string not complete), 120378456 or 0012345600
(multiple blocks in the string).
Rule 2: the shorter code is not filtered by rule 1. In the longer code, all possible
sub-strings of the same length as the shorter code string are compared with the
shorter code string. The shorter code is considered contained in the longer code if
the number of different characters between the compared codes is less than or
equal to the Max Number of Different Characters. The shorter code will be filtered
by rule 2.
Example:
If Max Number of Different Characters = 1:
The code 123456 is considered contained in the following codes: 12305600,
00123056, 8812305688 because there is only one different character in the
compared string.
The code 123456 is not considered contained in 123066789 because there are two
different characters in the compared string.
Max Number of Different Characters
Enter a value from 0 to 5 in the field provided to define the maximum number of
different characters allowed to still consider a code as being included in another
one and therefore to be filtered.
If the number of different characters between the compared codes exceeds the
value of this parameter, the codes are considered as different and will not be
filtered (a multiple read of a different code occurs).
If the number of different characters between the compared codes is less than or
equal to the value of this parameter, the short code is considered as a sub-string of
the longer code and will be filtered (no multiple read occurs).
If Max Number of Different Characters = 2:
The code 123456 read once, is considered the same as the following codes read
multiple times: 133056, 123546, 123457 because there are two or less different
characters by position in the compared codes.
The code 123456 read once, is not considered the same as the following codes
read multiple times: 153246, 103057, 654321 because there are at least three
different characters by position in the compared codes.
Voting Filter
Select the check box to reveal the Max Number of Different Characters <XREF>
field.
When checked, this filter attempts to eliminate false multiple reads by comparing
the number of different characters by position between two codes of the same type
and length. This condition implicates that reading a code of the same type and
length having very few different characters is probably a misread of the code itself
and therefore the code read the least number of times should be ignored, (should
not be considered as a multiple read of a different code).
This filter is based upon the following rules:
a multiple read condition occurs;
the two codes are of the same type;
the two codes have the same length;
the number of different characters by position is equal to or less than the
number defined by the Max Number of Different Characters parameter;
Message Tx Selection (see section ) must be set to After Reading Phase Off.
If the Contained Filter parameter is used when Message Tx Selection (see section ) is
set to On Decoding, the filter conditions may be satisfied before the reading phase
ends resulting in possible successive multiple read errors.