Human-Readable Text; Compressed Data Formats; Checksum Calculation - Lexmark T656 Technical Reference Manual

• The currentpoint is located at the bottom right corner of the bounding box when printing is
complete.
This currentpoint positioning applies both with and without accompanying human-readable text and
also considers any specified quiet zones to be within the bounding box.

Human-readable text

Human-readable text can be specified with one-dimensional bar codes under the following
provisions:
• The typeface to be used is specified with the /FontName key.
• The specified text is automatically centered on the bar code.
• Text is automatically scaled based on the width and height of the bar code and on the method
of embedding used.
Because two-dimensional bar codes are capable of encoding thousands of characters,
human-readable interpretation of the data may not be practical. Alternatively, descriptive text rather
than literal text may be printed with the symbol. If printed, any character size and font available may
be selected, and the text may be printed anywhere desired near the symbol. The text must not
interfere with the bar code symbol or its quiet zones.

Compressed data formats

Some bar code symbologies, such as UPC-E and Code 128, use compressed data formats. The
Forms and Bar Code Card accepts data for these symbologies in either compressed or
uncompressed format. The incoming data is analyzed to determine if it is compressed or not, and if
required, compression is automatically performed prior to printing the bar code.

Checksum calculation

Some bar code symbologies define checksum characters as a requirement of the data format. When
this is the case, the Forms and Bar Code Card performs the checksum calculation and automatically
places the character(s) per the symbology specifications. Fixed length data formats can be sent with
or without checksum characters.
PostScript emulation
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