Bar Code Horizontal Alignment; Pdf417 Capacity; Maxicode Separators And Structured Appends - Lexmark T656 Technical Reference Manual

Bar Code Horizontal Alignment

Certain UPC and EAN bar codes may not start at the existing PCL cursor position, but may be
shifted to the right up to 3-4mm on the left side, and up to 2mm on the right side. This is due to the
presence of "start" characters, which may or may not shift the bar code (and HRT) to the right.
If a customer allocates space for these particular bar codes, and they do not fit on the right side, then
there are 2 options:
• Use the PCL "B" and "S" parameters to slightly shrink the bar code in size.
• Escalate it for a field fix.

PDF417 Capacity

Please refer to the AIM PDF417 specification, which can be found here:
• http://lemming.sa.ap.lexmark.com/~tbarnett/files/AIM_PDF417_spec.pdf
In section 1 on pg. 1, the Introduction defines the Maximum Data Characters per symbol (at ECC0)
for PDF417:
• 1850 text characters
• 2710 digits
• 1108 bytes
Section 2.1 on pg. 2 states:
• "The total number of codewords in the data region of a single PDF417 symbol cannot exceed
928".
All input data should conform to the AIM PDF417 specification, and any input data over the maximum
lengths should be truncated and discarded. A maximum of 2710 digits or 1850 text characters should
be allowed and truncated by firmware before the BCE is called.
The remaining maximum data should be safely submitted to the BCE to be rendered. This will
require extra checking code to be added before the BCE, to truncate any excess data. However, this
procedure will prevent the BCE from throwing errors on pages with excess data, while encoding as
much of that data as possible.
The original LXK BCC will encode more than the maximum amount allowed by the AIM specification,
but users should never exceed these values. If users were to change to other printing equipment that
did not tolerate a marginally higher capacity, their process would be broken. Also, not all bar code
reading equipment may be capable of decoding data in excess of the maximum allowed in the AIM
PDF417 specification.

MaxiCode Separators and Structured Appends

Please refer to the AIM MaxiCode specifications found here:
• http://lemming.sa.ap.lexmark.com/weblog/2007/04/03#BarCodeSpecs
A valid MaxiCode data separator for MaxiCode data blocks is either:
Deviations
157