Define your printer¶
Before start creating your Python ESC/POS printer instance, you must see at your system for the printer parameters. This is done with the ‘lsusb’ command.
First run the command to look for the “Vendor ID” and “Product ID”, then 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 yields the “Interface” number that must be handy to have and the second yields the “Output Endpoint” address.
USB Printer initialization
Epson = 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 with your instance. So, assuming that we have another printer where in_ep is on 0x81 and out_ep=0x02, then the printer definition should looks like:
Generic USB Printer initialization
Generic = printer.Usb(0x1a2b,0x1a2b,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
Epson = printer.Network("192.168.1.99")
Must 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 hooked up.
Serial printer initialization
Epson = printer.Serial("/dev/tty0")
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 the initialize passing the device node name.
Epson = 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 demonstrate how to initialize the Epson TM-TI88IV on USB interface
from escpos import * """ Seiko Epson Corp. Receipt Printer M129 Definitions (EPSON TM-T88IV) """ Epson = printer.Usb(0x04b8,0x0202) # Print text Epson.text("Hello World\n") # Print image Epson.image("logo.gif") # Print QR Code Epson.qr("You can readme from your smartphone") # Print barcode Epson.barcode('1324354657687','EAN13',64,2,'','') # Cut paper Epson.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 programically.
The default configuration file is named
config.yaml. It’s in 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
search to the
To load the configured pritner, 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 paramter is
type. The value of this should be one of the
printers defined in Printers.
The rest of the parameters are whatever you want to pass to the printer.
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
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:
How to update your code for USB printers¶
Epson = escpos.Escpos(0x04b8,0x0202,0)
Epson = printer.Usb(0x04b8,0x0202)
Nothe that “0” which is the interface number is no longer needed.