CODE
11 SYMBOLOGY
CODE 11 SYMBOLOGY INTRODUCTION
Code 11 only
can encode numeric data(0 to 9),the dash symbol(-). It is also
known as USD-8, was developed as a high-density numeric-only symbology.
It is used primarily in labeling telecommunications equipment.Code
11 uses one or two weighted checksum digits. Normally if the length
of the message is less than 10 characters, one checksum "C" is
used. Otherwise both "C" and "K" are used.
Code 11 is
a discrete symbology. Characters are separated by an inter-character
gap which typically has the same width as the narrow element. The
height of the bars must be at least 0.15 times of the symbol��s
length or 0.25 inches, whichever is larger. The
name derives from the way that the ��C�� checksum digit is calculated.
For details, read further to the checksum section. Although
Code 11 is discrete, it is not self-checking because a single
printing defect can transpose one character into another valid
character.
Code
11 CheckSum Digits Calculation
To calculate
the optional checksum digit, follow the following steps:
-
Start
with the right-most digit in the message; assign the weight
starting with 1. Move from the right to left, and increment
the weight by one. A dash has a value of 10.
- Multiply
the character value by the weight and add the result together.
- Divide
the total result by 11. The remainder is the "C" checksum digit.
- If the
length of the message is greater than 10, you have to calc the "K" digit as well.
- Start
with the right most digit in the message (Now it should be "C"
digit). Repeat the step 1. This time divide the result by 9.
The remainder becomes the "K" checksum digit.
CODE 11 BARCODE STRUCTURE
-
A start
character.
- Encoded
Data.
- An optional
'C' check digit .
- An optional
'K' check digit .
- A stop
character.
INDUCTRIAL
2 OF 5 SYMBOLOGY
INDUCTRIAL
2 OF 5 SYMBOLOGY
"Industrial
2 of 5" is another name of "Standard 2 of 5", Standard
2 of 5 is a low-density numeric symbology that has been with us
since the 1960s. It has been used in the photofinishing and warehouse
sorting industries, as well as sequentially numbering airline
tickets.
Check
Digit Calculation
Standard
2 of 5 may include an optional modulo 10 check digit as the following
step:
1.Start with the right-most digit in the message; mark the character
with even and odd position. The right-most digit has the even
position.
2. Sum all
digits in the odd position;
3. Sum all
digits in the even position, and then multiply by 3.
4. Add the
result 2 and result 3;
5. Divide
the result of step 4 by 10, the check digit is the result equal
to that 10 minus the remainder.
Code25 symbol Structure
-
A start
character
- Data
encoded
- Optional
Mod 10 check digit
- A stop
character
INTERLEAVED
2 OF 5 SYMBOLOGY
INTERLEAVED 2 OF 5 INTRODUCTION
Interleaved
2 of 5 is a higher-density numeric symbology based upon the Standard
2 of 5 symbology. It is used primarily in the distribution and
warehouse industry.
Interleaved
2 of 5 encodes any even number of numeric characters in the widths
(either narrow or wide) of the bars and spaces of the barcode.
Unlike Standard 2 of 5, which only encodes information in the
width of the bars, Interleaved 2 of 5 encodes data in the width
of both the bars and spaces. This allows Interleaved 2 of 5 to
achieve a somewhat higher density.
The symbology
is called "interleaved" because the first numeric data is encoded
in the first 5 bars while the second numeric data is encoded in
the first 5 spaces that separate the first 5 bars. Thus the first
5 bars and spaces actually encode two characters. This is also
why the barcode can only encode an even number of data elements.
INTERLEAVED 2 OF 5 CHECKSUM DIGIT CALCULATION
Interleaved 2 of 5 is similar to Standard 2 of 5 in the sense that
it may include an optional modulo 10 check digit. The process for
calculating the check digit is the same in Interleaved 2 of 5 as
it is in Standard 2 of 5. And, like Standard 2 of 5, the checksum
digit is optional.
AN INTERLEAVED 2 OF 5 BARCODESTRUCTURE
-
Start character, encoded as 1010.
-
Each pair of data characters is encoded.
-
Stop character, encoded as 1101.
MSI
SYMBOLOGY
MSI
INTRODUCTION
MSI was developed
by the MSI Data Corporation, based on the original Plessey Code.
MSI, also known as Modified Plessey, is used primarily to mark
retail shelves for inventory control. MSI is a continuous, non-self-checking
symbology. While the length of an MSI barcode can be of any length,
a given application usually implements a fixed-length code.
MSI, and
other symbologies based on Pulse-Width Modulation, offer no significant
benefit over more modern symbologies. While it is not a bad idea
to support MSI for legacy barcodes, most new applications do not
choose MSI as their symbology of choice.
COMPUTING THE CHECKSUM DIGIT
MSI uses one or two
check digits, which may be calculated in a number of different
ways. As such, it is really up to the software application to
implement and check the check digit(s).
To calculate the modulo 10 checksum digit, use the following steps:
- Create
a new number using every other digit from the original code
such that the right-most digit of the new number is the right-most
digit of the old number. For example, in the barcode above
the data we encoded was "8052". In this case, the "new number" is 02.
- Take
the new number calculated in step 1 and multiply it by 2.
In this case, 02 * 2 is 4.
- Add
the digits of the value calculated in the previous step (4),
and add it to the digits that were not used in step 1 to form
the new number. In our example, this would be 4 + 8 + 5 =
17. The "4" comes from step 2, the 8 and 5 come from the "8052" and are the digits that weren't used to form the new number
in step 1. If the result from step 2 were, for example, 123,
then we'd add 1 + 2 + 3 = 6 (plus the digits that weren't
used from step 1).
- Do a
modulo 10 calculation on the result of step 3. In this case,
17 modulo 10 = 7.
- The
check digit is the value which, added to the result in step
4, equals 10. In this case, we must add 3 to 7 to get 10-so
the check digit is 3. This explains why the example barcode
above has a trailing "3" on it.
AN MSI BARCODE STRUCTURE
- A start
character which is a wide bar followed by a narrow space.
- Encoded
Data.
- Checksum
digit(s).
- A stop
character, which is a narrow bar, a wide space, then a narrow
bar.
CODABAR
SYMBOLOGY
CODABAR INTRODUCTION
Codabar was
developed was developed in 1972 by Pitney Bowes, Inc. It is a
discrete, self-checking symbology that may encode 16 different
characters, plus an additional 4 start/stop characters. This symbology
is used by U.S. blood banks, photo labs, and on FedEx airbills.
Since Codabar
is self-checking, there is no established checksum digit. Should
a specific application wish to implement a checksum digit for
additional security, it is up to the implementer to define and
handle same. However, keep in mind that other applications that
read your barcode will interpret your checksum digit as part of
the message itself.
A
Codabar Barcode structure:
-
One of
four possible start characters (A, B, C, or D), encoded from
the table below.
-
A narrow,
inter-character space.
-
The data
of the message, encoded from the table below, with a narrow
inter-character space between each character.
-
One of
four possible stop characters (A, B, C, or D), encoded from
the table below.
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