Code 128 Subset Switching - Microcom 334M Operator's Manual

Chapter 8
The
printer
defaults to
subset B
Subset A
This subset contains 106 unique characters, which includes numbers 0 through 9, the
English alphabet (uppercase only), punctuation marks, ASCII control codes, and the special
function codes listed in tables above.
Subset B
This subset contains 106 unique characters, which includes numbers 0 through 9, the
English alphabet (both uppercase and lower case), punctuation marks, and the special
function codes listed in tables above. This is the default if a subset is not defined when
using manual compression.
Subset C
This subset contains 106 unique characters, which includes matched pair numbers 00
through 99 and the special function codes listed in table 16. Subset C requires that an even
amount of digits to be sent because the matched pairs are encoded as a single character.
This allows for a greater amount of compression than subsets A and B. If an odd amount of
digits and/or non-numeric characters were sent while using subset C, the resulting bar code
produced would be invalid.
8.1.16 Codabar (Rationalized), TCI 42
Codabar is a variable length linear symbology that is commonly used in libraries, blood
banks, and in the air parcel business. Codabar is capable of encoding the 16 following
characters: 0123456789-$:/. + and the four start/stop characters ABCD. This symbology
uses 2:1, 3:1, 4:2, 5:2, and 8:3 ratios, which may be selected using the CGN parameter.
8.1.17 Code 93, TCI 43
Code 93 is a variable length, alphanumeric symbology that is capable of encoding 48
different characters and through the use of control characters can encode the full 128 ASCII
character set. The 48 characters include the "space", numerical characters 0 through 9, the
English alphabet (uppercase only), characters $%+-. / along with five special characters
including the start/stop character.
8.1.18 PDF-417, TCI 46
The Portable Data File 417 or PDF-417 is a two-dimensional stacked symbology that is
capable of encoding the entire ASCII character set, 2710 digits, and up to 1108 bytes in a
single bar code. The requirements for generating a PDF-417 symbology are the text data,
334M Operator's Manual - 880060-0110
ABC#3012345#5abc
The "#3"
code, while
in subset B,
switches to
subset C.
Figure 8-8

Code 128 Subset Switching

The "#5"
code,
while in
subset C,
switches
Bar Codes
8-8