Symbol Technologies P 300STD Photo Scanner User Manual


 
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P 300STD/FZY/PRO Scanner Product Reference Guide
Transmit Symbols in Codeword Format
Enabling this activates transmission of each PDF symbol as directly decoded data codewords,
whether that symbol is part of a macro PDF sequence or not. Note that data is output as
codeword values
not
as interpreted data
.
“Codeword values” is an ASCII representation of a number from 000 to 928 for each
codeword, preceded by an escape character. This escape character is a backslash by default,
but the user may change this value. For example, the codeword value 005 is sent to the host
in the form of
\005
for GLIs, and
\C005C
for ECIs. This output format is based on the
AIM
USA Uniform Symbology Specification
for PDF417 (1994).
All output codewords take up exactly 4 characters for GLIs and 6 characters for ECIs.
However, there may be non-decodable characters in the PDF symbol, such as a GLI sequence.
This special codeword sequence activates a certain kind of interpretation to the encoded data.
Non-decodable codewords like GLIs are embedded in the output stream just like any other
codeword, e.g., \927\001.
Because GLIs are indistinguishable from other codewords in the output data stream, the host
must intelligently recognize them as GLIs and process their interpretations.
Note that when a macro PDF sequence is transmitted, the last character in the last block of
data transmitted is always
\922
(if selected). This indicates the end of that macro PDF
transmission.