Specifications

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ZB64 Encoding and Compression
Introduction to B64 and Z64
9/15/06 ZPL II Programming Guide 45541L-004 Rev. A
The parameters are identical to the existing ~DT command:
When downloading graphics, the colon is used in the current ASCII hexadecimal encoding
indicate “repeat the previous dot row.” Since this shorthand is invalid for the first character of
data (no previous dot row has been downloaded), it is safe for the printer to detect the leading
colon character as the lead-in for the new encodings.
Table 23 • ~DT Command Parameters
Parameter Details
o = font name
Accepted Values: any valid TrueType name, up to 8 characters
Default Value: if a name is not specified, UNKNOWN is used
In this example, Arial is the specified font.
s = font size
Accepted Values: the number of memory bytes required to hold
the Zebra-downloadable format of the font
Default Value: if an incorrect value or no value is entered, the
command is ignored
In this example, 59494 is the size.
To maintain compatibility with the existing ASCII hexadecimal
encoding, this field must contain the size of the un-enclosed and
uncompressed object — the number of bytes that are finally
placed into the printer’s memory, not the number of bytes
downloaded.
data = data string
Accepted Values: a string of ASCII hexadecimal values (two
hexadecimal digits/byte). The total number of two-digit values
must match parameter
s.
Default Value: if no data is entered, the command is ignored
Everything following the size field is data. The new encoding
imposes a header with a unique signature. The new encoding must
start with the characters :B64: (data encoded in Base-64 only) or
:Z64: (data compressed with LZ77, then encoded in Base-64)
followed by the encoded data.
After the data is presented, another colon (:) and four hexadecimal
digits comprise the CRC. The Base64 standard allows new-line
characters (carriage returns and line feeds) to be inserted into the
encoded data for clarity. These characters are ignored by the
printer.