Worth Data TriCoder t53, Руководство пользователя

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N-1
Appendix N
Code 93 Specifications
Code 93 is variable length, continuous, bi-directional, compact code. Code 93 is
an alphanumeric bar code which consists of
43 data characters ( 0-9 , A-Z , $/+%.-
and Space ), 4 control characters , and a unique start/stop character . The entire
set of 128 ASCII characters is represented in Code 93 using combinations of
control characters and data characters .
The control characters are , , , and . Full ASCII 93 is created by
pairing these control characters with normal data characters. It is almost
identical to the pairings for Code 39; Code 39 uses $M to produce a Carriage
Return (ASCII 13) character -- Code 93 uses M to produce the Carriage
Return.
Code 93's two built-in check digits greatly minimize the possibility of reader
substitution errors. These check digits are never transmitted by the bar code
reader. Code 93's Start and Stop characters are also never transmitted.
The Code 39 features of Accumulate Mode , Caps Lock ON and Caps lock
OFF also apply to Code 128.
If you have not decided which bar code type to use for your application and are
considering using Code 93, while we agree that Code 93 is an excellent code, we
believe that Code 128 is generally preferable because less space is required.
Two space disadvantages of Code 93 are:
1. Code 93 does not have the numeric compression capability that
128 does, (compression results in 128’s significantly less space
for equivalent codes), and
2. Code 93 requires pairings to make all Full ASCII characters
while 128 does not, (more space is required for lower case and
upper case than Code 128).