Barcode Scanning
Code 11, also known as USD-8, is a high-density, discrete symbology that is primarily used for the labeling of telecommunications equipment. It was invented by David Allais of Intermec Corporation in 1977.
Symbol Structure
The symbol comprises the following elements:
Start character
Symbol characters that represent data
Optional checksum digits
Stop character
The first and last element of every character is a bar. A one-module intercharacter space is added to separate characters from one another.
Character Set
This symbology supports the numeric digits (0-9) and the hyphen character (-). Code 11 derives its name from these 11 characters.
Checksum Digits
Because of the natural density of Code 11, printing imperfections can cause scanners to misread characters. To compensate for this limitation, Code 11 supports the use of one or two optional checksum digits. For data inputs that have fewer than 10 numeric characters, a single checksum digit is used, and for 10 or more digits, two checksum digits are used. The first digit is based on the modulo 11 algorithm, and the second is based on the modulo 9 algorithm.
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