Code 128 - Intermec 700 Series User Manual

APPENDIX C Bar Codes
Code 93
The introduction of Code 93 provided a higher density alphanumeric symbology
designed to supplement Code 39. The set of data characters in Code 93 is identi-
cal with that offered with Code 39. Each character consists of nine modules ar-
ranged into three bars and three spaces.
Code 93 uses 48 of the 56 possible combinations. One of these characters, repre-
sented by a square, is reserved for a start or stop character, four are used for con-
trol characters, and the remaining 43 data characters coincide with the Code 39
character set. An additional single module termination bar after the stop char-
acter concludes the final space.
Code 93 is a variable length, continuous code that is not self-checking. Bar and
spaces widths may be one, two, three, or four modules wide. Its structure uses
edge-to-similar-edge decoding. This makes the bar code immune to uniform ink
spread, which allows liberal bar width tolerances.
Code 93 uses two check characters. Its supporters believes this makes it the
highest density alphanumeric bar code. The dual check digit scheme provides for
high data integrity. All substitution errors in a single character are detected for
any message length.

Code 128

Code 128 (C128) is one of the newest symbologies used by the retail and
manufacturing industries. It responds to the need for a compact alphanumeric
bar code symbol that could encode complex product identification.
The fundamental requirement called for a symbology capable of being printed by
existing data processing printers (primarily dot-matrix printers) that produce
daily, work-in-progress, job, and product traceability documents. The ability to
print identification messages between 10 and 32 characters long, on existing
forms and labels deemed an important requirement.
Code 128 uniquely addresses this need as the most compact, complete, alphanu-
meric symbology available.
Additionally, the Code 128 design with geometric features, improves scanner
read performance, does self-checking, and provides data message management
function codes.
Code 128 encodes the complete set of 128 ASCII characters without adding extra
symbol elements. Code 128 contains a variable-length symbology and the ability
to link one message to another for composite message transmission. Code 128,
being a double-density field, provides two numeric values in a single character.
Code 128 follows the general bar code format of start zone, data, check digit, stop
code, and quiet zone. An absolute minimum bar or space dimension of nine mils
(0.010 inch minimum nominal ± 0.001 inch tolerance) must be maintained.
Characters in Code 128 consist of three bars and three spaces so that the total
character set includes three different start characters and a stop character.
UCC/EAN-128 Shipping Container Labeling is a versatile tool that can ease
movement of products and information. The Shipping Container Labeling bar
code can take any form and usually has meaning only within the company or fa-
cility where applied.
700 Series Color Mobile Computer User's Manual C-5