Lexmark T656 Technical Reference Manual page 161

Gs: hex 1D, decimal 29
comma: hex 2C, decimal 44
This will be used in the discussions below.
1
MaxiCode Typeface Call method
The existing Bar Code Technical Reference manual ver 2.4b, and the HP BarDIMM Technical
Reference manual from 3.0 onward are in conflict over how the separator works, and how
Mode 2 and Mode 3 is specified.
A Structured Append is covered in the MaxiCode AIM specification, which allows up to eight
MaxiCode symbols to be chained together as one. However, the reality is that there are no
bar code readers that can decode such a combined bar code series.
The SuchyMIPS BCE does support Structured Appends, and so does HP BDP. That is, they
can parse the structured append (described below), but they do not fully implement it.
A structured Append consists of 4 bytes that are:
• A number 1 through 8, that labels each individual MaxiCode in the Structured Append.
• A separator character, either a comma or a Gs (which is ASCII 29).
• A number 1 through 8, that represents the maximum number of MaxiCode symbols in the
Structured Append.
• Another separator character.
For example, the only valid MaxiCode that is supported should be a single symbol, specified
as:
1,1,01234567...... where 1,1, represents the Structured Append; and 01234567.... represents
the rest of the MaxiCode data structure.
The HP spec BarDIMM specification version 3.0 (and all versions from then on) is consistent
with this PCL datastream calling sequence:
<Esc>(s24800T1,1,x,01234567..... where x is either a 2 or 3, corresponding to MaxiCode
Mode 2 or Mode 3
Mode 2 encodes numeric-only data, and Mode 3 allows a reduced amount of alphanumeric
data.
Note that the Mode of the MaxiCode is specified within the input data, after the typeface
command 24800T. If the 2 extra bytes (Mode number 2 or 3, plus a separator) are included in
the input data, the BCE will throw an error.
Users should add additional parsing that examines input data:
• Byte 5 for either a "2" or a "3"
• Byte 6 for a separator character
If they are found, remove them, and pass the 4 Structured Append bytes and the rest of the
input data to the BCE. This method will still allow existing HP-coded datastreams to work on
HP BDP, while allowing the Forms and Bar Code Card to work correctly, as well.
Deviations
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