Beyond 1s and 0s

Team name:

Barcode

* Original question:

How would the string CSE370 be represented at the physical level in barcode?

* Exact question:

How is the string CSE370 represented in Code 39 barcode?

* What are ?

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.)

* Major types of barcode:

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.

* How is code 39 encoded?

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