Define your printer¶
Before creating your Python ESC/POS printer instance, consult the system to obtain the printer parameters. This is done with the ‘lsusb’ command.
Run the command and look for the “Vendor ID” and “Product ID” and write down the values. These values are displayed just before the name of the device with the following format:
# lsusb Bus 002 Device 001: ID 04b8:0202 Epson ...
Write down the the values in question, then issue the following command so you can get the “Interface” number and “End Point”
# lsusb -vvv -d xxxx:xxxx | grep iInterface iInterface 0 # lsusb -vvv -d xxxx:xxxx | grep bEndpointAddress | grep OUT bEndpointAddress 0x01 EP 1 OUT
The first command will yield the “Interface” number that must be handy to have and the second yields the “Output Endpoint” address.
USB Printer initialization
p = printer.Usb(0x04b8,0x0202)
By default the “Interface” number is “0” and the “Output Endpoint” address is “0x01”. If you have other values then you can define them on your instance. So, assuming that we have another printer, CT-S2000, manufactured by Citizen (with “Vendor ID” of 2730 and “Product ID” of 0fff) where in_ep is on 0x81 and out_ep=0x02, then the printer definition should look like:
Generic USB Printer initialization
p = printer.Usb(0x2730, 0x0fff, 0, 0x81, 0x02)
You only need the IP of your printer, either because it is getting its IP by DHCP or you set it manually.
Network Printer initialization
p = printer.Network("192.168.1.99")
Most of the default values set by the DIP switches for the serial printers, have been set as default on the serial printer class, so the only thing you need to know is which serial port the printer is connected to.
Serial printer initialization
p = printer.Serial("/dev/tty0") # on a Windows OS serial devices are typically accessible as COM p = printer.Serial("COM1")
Some printers under /dev can’t be used or initialized with any of the methods described above. Usually, those are printers used by printcap, however, if you know the device name, you could try to initialize by passing the device node name.
p = printer.File("/dev/usb/lp1")
The default is “/dev/usb/lp0”, so if the printer is located on that node, then you don’t necessary need to pass the node name.
Define your instance¶
The following example demonstrates how to initialize the Epson TM-TI88IV on a USB interface.
from escpos import * """ Seiko Epson Corp. Receipt Printer M129 Definitions (EPSON TM-T88IV) """ p = printer.Usb(0x04b8,0x0202) # Print text p.text("Hello World\n") # Print image p.image("logo.gif") # Print QR Code p.qr("You can readme from your smartphone") # Print barcode p.barcode('1324354657687','EAN13',64,2,'','') # Cut paper p.cut()
You can create a configuration file for python-escpos. This will allow you to use the CLI, and skip some setup when using the library programmatically.
The default configuration file is named
config.yaml and uses the YAML
format. For windows it is probably at:
And for linux:
If you aren’t sure, run:
from escpos import config c = config.Config() c.load()
If it can’t find the configuration file in the default location, it will tell
you where it’s looking. You can always pass a path, or a list of paths, to
To load the configured printer, run:
from escpos import config c = config.Config() printer = c.printer()
The printer section¶
printer configuration section defines a default printer to create.
The only required parameter is
type. The value of this has to be one of the
printers defined in Printers.
The rest of the given parameters will be passed on to the initialization of the printer class. Use these to overwrite the default values as specified in Printers. This implies that the parameters have to match the parameter-names of the respective printer class.
An example file printer:
printer: type: File devfile: /dev/someprinter
And for a network printer:
printer: type: Network host: 127.0.0.1 port: 9000
An USB-printer could be defined by:
printer: type: Usb idVendor: 0x1234 idProduct: 0x5678 in_ep: 0x66 out_ep: 0x01
Printing text right¶
Python-escpos is designed to accept unicode.
For normal usage you can simply pass your text to the printers
text()-function. It will automatically guess
the right codepage and then send the encoded data to the printer. If this feature does not work, please try to
isolate the error and then create an issue on the GitHub project page.
If you want or need to you can manually set the codepage. For this please use the
charcode()-function. You can set
any key-value that is in
CHARCODE. If something is wrong, an
CharCodeError will be raised.
After you have manually set the codepage the printer won’t change it anymore. You can revert to normal behaviour
by setting charcode to
Advanced Usage: Print from binary blob¶
Imagine you have a file with ESC/POS-commands in binary form. This could be useful for testing capabilities of your printer with a known working combination of commands. You can print this data with the following code, using the standard methods of python-escpos. (This is an advantage of the fact that _raw() accepts binary strings.)
from escpos import printer p = printer.Serial() # adapt this to your printer model file = open("binary-blob.bin", "rb") # read in the file containing your commands in binary-mode data = file.read() file.close() p._raw(data)
That’s all, the printer should then print your data. You can also use this technique to let others reproduce an issue that you have found. (Just “print” your commands to a File-printer on your local filesystem.) However, please keep in mind, that often it is easier and better to just supply the code that you are using.
Here you can download an example, that will print a set of common barcodes:
Advanced Usage: change capabilities-profile¶
Packaged together with the escpos-code is a capabilities-file. This file in JSON-format describes the capabilities of different printers. It is developed and hosted in escpos-printer-db.
Certain applications like the usage of cx_freeze might change the packaging structure. This leads to the capabilities-profile not being found. In this case you can use the environment-variable ESCPOS_CAPABILITIES_FILE. The following code is an example.
# use packaged capabilities-profile python-escpos cut # use capabilities-profile that you have put in /usr/python-escpos export ESCPOS_CAPABILITIES_FILE=/usr/python-escpos/capabilities.json python-escpos cut # use packaged file again unset ESCPOS_CAPABILITIES_FILE python-escpos cut
Hint: preprocess printing¶
Printing images directly to the printer is rather slow. One factor that slows down the process is the transmission over e.g. serial port.
Apart from configuring your printer to use the maximum baudrate (in the case of serial-printers), there is not much
that you can do.
However you could use the
escpos.printer.Dummy-printer to preprocess your image.
This is probably best explained by an example:
from escpos.printer import Serial, Dummy p = Serial() d = Dummy() # create ESC/POS for the print job, this should go really fast d.text("This is my image:\n") d.image("funny_cat.png") d.cut() # send code to printer p._raw(d.output)
This way you could also store the code in a file and print it later. You could then for example print the code from another process than your main-program and thus reduce the waiting time. (Of course this will not make the printer print faster.)