CSE 370 Autumn 2001
Mini research project
11/02/2001
Team name:
How would the string CSE370 be represented at the physical level in barcode?
How is the string CSE370 represented in Code 39 barcode?
Barcodes are the most common kinds of ID technology providing timely,
error-free information which can be used to accurately
verify routine business transactions and increase productivity. The most
commonly used barcodes are symbols which use a series of bars and spaces to
encode characters (letters, numbers, special characters, etc.)
There
are many kinds of barcodes. In this
paper, we only list some of the most popular ones.
1. U.P.C.
(Universal Product Code) is one of the most popular types of bar code in the US. It is widely used in most of retail product.
2. E.A.N. (European Article Number) is not commonly used in the U.S., but is used by countries other than the United States for identification on retail goods
3. Code 3 of 9 (also known as USS Code 39 or Code 39) is used for various barcoding labels such as name badges, inventory and industrial applications. Code 39 is also used by the government, especially the Department of Defense.
4. Interleaved 2 of 5 (I 2/5) is a numeric only barcode used for encoding pairs of numbers in a high density barcode format.
5. Code 128 is a very high density alphanumeric bar code, and is designed to encode all 128 ASCII characters.
6. Postnet (POSTal Numerical Encoding Technique): This code is developed by the US Postal Service to encode ZIP code information on letter mail.
7. Pharmacode
is mainly used in packing control systems.
*
Why do we choose code 39?
Among
all the bar code symbologies, we chose Code 39 to represent "CSE370",
because it can represent both letters and numbers, and it is very easy to
encode.
Code 39 barcode symbology supports 43 characters and an
additional character which is used as a delimiter or start/stop character. The
43 characters include:
1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ - . $ / + % SPACE
In Code 39, all letters are upper case. This means
"CSE370" and "cse370" have the same representation.
In order to use lower case letters or other ASCII characters you need to
use Extended Code 39, which you can find in: http://www.barcodeman.com/info/c39_ext.php3
Interestingly, all the computers
in CSE lab are labeled with code 39 barcode.
Code 39 contains a series of bars that represent different characters. Each character is encoded using nine bars—five black bars and the four white bars. The white bars are spaces between the black bars. It is required that three of the nine bars must be wider than the others. In order to increase decoding accuracy, it is recommended to make the wide bars 3 times wider than the thin bars.
Code
39 begins and ends with a start and a stop character—
* .
From
the TABLE OF CONFIGURATIONS
you can check out
how each character is represented using 1s and 0s and also the exact barcode
representation. A
space (thin white bar) is used between each character to separate them.
Check
digit
Some
applications may use a check digit along with the code, but it is not often
used. Check digit is modulus
43 sum of all character values in the string. The value for each character is
specified by the sequence: 0 = 0, ..., 9 = 9, A = 10, B = 11, ..., Z = 35, - =
36, .
= 37, space = 38, $ = 39, / = 40, + = 41, % = 42.
For
example, the string AZ6 would have the check value (10+35+6) mod 43 =
11, that is letter B. The string
now becomes *AZ6B*.
A
check digit is not needed to represent the string CSE370, so we only need to
encode *CSE370* into barcode.
Below is the barcode for the string CSE370 from the TABLE OF CONFIGURATIONS
Pattern
Bars Spaces
*
00110
1000
C
11000
0010
S 01010 0001
E 10100 0010
3 11000 0100
7 00011 0100
0 00110 0100
Source:
http://www.barcodeman.com/info/c39_1.php3