Worth Data RF Laser user manual Code 128 Specifications, UCC-128/ EAN-128

Appendix F

Code 128 Specifications

Code 128 is a very powerful bar code, combining an extensive character set and variable length with compactness and error checking. The character set contains all 128 ASCII characters with each character made up of three bars and three spaces. Each element (bar or space) varies from one to four units in width, totaling 11 units of width per character. Code 128 contains two levels of error checking:

•Each character is checked for internal parity, and

•The last character is a checksum.

Code 128 has three subsets, A, B and C. Subset A contains alphanumeric characters and unprintable control characters, subset B contains alphanumeric characters plus printable control characters and subset C contains only numeric characters and uses a 2-character

12345 encoding scheme to create a more compact bar code. Code 128 uses an internal Mod 103 check character that

is not displayed by the bar code reader. Code 128 bar codes can be made up of only one subset or may be a combination of several.

The Code 39 features of Accumulate Mode, Caps Lock ON and Caps lock OFF also apply to Code 128.

UCC-128/ EAN-128

UCC-128/EAN-128 Code is a subset of Code 128 adopted by the UCC and EAN council’s for use as a shipping label symbology. UCC/EAN-128 bar codes always start with a Function Code 1 character. In addition, all variable length fields are terminated by a Function Code 1 character unless they are the last field in the bar code.

The RF Laser Reader outputs the following for the special function codes and start sequences:

]C1	Start C/Function Code 1
^]	(GS) Function Code 1 as a variable string terminator

If UCC/EAN 128 is enabled, the reader looks for the Start C/Function Code 1 to indicate a UCC/EAN 128 bar code.

The UCC Serial Shipping Container Code specification calls for a 19 digit UCC/EAN 128 code with an additional Mod 10 Check digit (20 digits in all).

37