2b62c8e28d
* disable system packages on rtd * install pycups on rtd * enable cups binding in documentation * document CupsPrinter * fix formatting * revise methods and installation * revise user/printers * revise raspi section * further revise
48 lines
1.6 KiB
ReStructuredText
48 lines
1.6 KiB
ReStructuredText
Printing Barcodes
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-----------------
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:Last Reviewed: 2023-08-10
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Many printers implement barcode printing natively.
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This hardware renderered barcodes are fast but the supported
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formats are limited by the printer itself and different between models.
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However, almost all printers support printing images, so barcode
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rendering can be performed externally by software and then sent
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to the printer as an image.
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As a drawback, this operation is much slower and the user needs
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to know and choose the image implementation method supported by
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the printer's commandset.
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barcode-method
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~~~~~~~~~~~~~~
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Since version 3.0, the ``barcode`` method unifies the previous
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``barcode`` (hardware) and ``soft_barcode`` (software) methods.
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It is able to choose automatically the best printer implementation
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for barcode printing based on the capabilities of the printer
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and the type of barcode desired.
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To achieve this, it relies on the information contained in the
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escpos-printer-db profiles.
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The chosen profile needs to match the capabilities of the printer
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as closely as possible.
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.. py:currentmodule:: escpos.escpos
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.. automethod:: Escpos.barcode
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:noindex:
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CODE128
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~~~~~~~
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Code128 barcodes need a certain format.
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For now the user has to make sure that the payload is correct.
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For alphanumeric CODE128 you have to preface your payload with `{B`.
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.. code-block:: Python
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from escpos.printer import Dummy, Serial
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p = Serial()
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# print CODE128 012ABCDabcd
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p.barcode("{B012ABCDabcd", "CODE128", function_type="B")
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A very good description on CODE128 is also on
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`Wikipedia <https://en.wikipedia.org/wiki/Code_128>`_.
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