Specifications

ZB64 Encoding and Compression
B64 and Z64 Encoding
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45541L-004 Rev. A ZPL II Programming Guide 9/15/06
B64 and Z64 Encoding
These download encodings, B64 and Z64, are created as drop-in replacements for the existing
ASCII hexadecimal encoding.
B64 encoding do the following:
• Encode the compressed data using the MIME Base64 algorithm.
• Calculate a CRC across the encoded data.
• Add a unique header to differentiate the new format from the existing ASCII hex
encoding.
Z64 encoding do the following:
• Compress the data using the LZ77 algorithm.
• Encode the compressed data using the MIME Base64 algorithm.
• Calculate a CRC across the encoded data.
• Add a unique header to differentiate the new format from the existing ASCII hexadecimal
encoding.
The data field have this format:
:id:encoded_data:crc
This table identifies the parameters for this format:
The printer calculates a CRC across the received data bytes and compare this to the CRC in the
header. A CRC mismatch is treated as an aborted download.
The B64 and Z64 encodings can be used in place of the ASCII hexadecimal encoding in any
download command. The commands are:
~DB – Download Bitmap Font
~DE – Download Encoding
~DG – Download Graphic
~DL – Download Unicode Bitmap Font
~DS – Download Scalable Font
~DT – Download TrueType Font
~DU – Download Unbounded TrueType Font
^GF – Graphic Field (with compression type set to “ASCII hex”)
Table 24 • Format Parameters
Parameter Details
:id the identifying string B64 or Z64
:iencoded_data data to download, compressed with LZ77 (if the id parameter is
set to Z64) and encoded with Base64.
:crc four hexadecimal digits representing the CRC calculated over the
:encoded_data field.