Printers
========

:Last Reviewed: 2022-11-25

As of now there are 7 different type of printer implementations.

USB
---
The USB-class uses pyusb and libusb to communicate with USB-based
printers. Note that this driver is not suited for USB-to-Serial-adapters
and similiar devices, but only for those implementing native USB.

.. autoclass:: escpos.printer.Usb
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    :member-order: bysource
    :noindex:

Serial
------
This driver uses pyserial in order to communicate with serial devices.
If you are using an USB-based adapter to connect to the serial port,
then you should also use this driver.
The configuration is often based on DIP-switches that you can set on your
printer. For the hardware-configuration please refer to your printer's manual.

.. autoclass:: escpos.printer.Serial
     :members:
     :special-members:
     :member-order: bysource
     :noindex:

Network
-------

This driver is based on the socket class.

.. autoclass:: escpos.printer.Network
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Troubleshooting
^^^^^^^^^^^^^^^
Problems with a network-attached printer can have numerous causes. Make sure that your device has a proper IP address.
Often you can check the IP address by triggering the self-test of the device. As a next step try to send text
manually to the device. You could use for example:

    ::

            echo "OK\n" | nc IPADDRESS 9100
            # the port number is often 9100

As a last resort try to reset the interface of the printer. This should be described in its manual.

File
----
This printer "prints" just into a file-handle. Especially on \*nix-systems this comes very handy.

.. autoclass:: escpos.printer.File
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Dummy
-----
The Dummy-printer is mainly for testing- and debugging-purposes. It stores
all of the "output" as raw ESC/POS in a string and returns that.

.. autoclass:: escpos.printer.Dummy
      :members:
      :member-order: bysource
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CUPS
----
This driver uses `pycups` in order to communicate with a CUPS server.
Supports both local and remote CUPS printers and servers.
The printer must be properly configured in CUPS administration.
The connector generates a print job that is added to the CUPS queue.

.. todo:: fix import in documentation

LP
----
This driver uses the UNIX command `lp` in order to communicate with a CUPS server.
Supports local and remote CUPS printers.
The printer must be properly configured in CUPS administration.
The connector spawns a new sub-process where the command lp is executed.

No dependencies required, but somehow the print queue will affect some print job such as barcode.

.. autoclass:: escpos.printer.LP
      :members:
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      :member-order: bysource
      :noindex: