648 lines
22 KiB
Python
648 lines
22 KiB
Python
#!/usr/bin/python
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""" Main class
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This module contains the abstract base class :py:class:`Escpos`.
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:author: `Manuel F Martinez <manpaz@bashlinux.com>`_ and others
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:organization: Bashlinux and `python-escpos <https://github.com/python-escpos>`_
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:copyright: Copyright (c) 2012 Bashlinux
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:license: GNU GPL v3
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"""
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try:
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import Image
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except ImportError:
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from PIL import Image
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import qrcode
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import textwrap
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import binascii
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import operator
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from .constants import *
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from .exceptions import *
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from abc import ABCMeta, abstractmethod # abstract base class support
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class Escpos(object):
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""" ESC/POS Printer object
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This class is the abstract base class for an esc/pos-printer. The printer implementations are children of this
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class.
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"""
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__metaclass__ = ABCMeta
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device = None
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def __init__(self, columns=32):
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""" Initialize ESCPOS Printer
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:param columns: Text columns used by the printer. Defaults to 32."""
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self.columns = columns
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@abstractmethod
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def _raw(self, msg):
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""" Sends raw data to the printer
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This function has to be individually implemented by the implementations.
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:param msg: message string to be sent to the printer
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"""
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pass
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@staticmethod
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def _check_image_size(size):
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""" Check and fix the size of the image to 32 bits
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:param size: size of the image
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:returns: tuple of image borders
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:rtype: (int, int)
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"""
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if size % 32 == 0:
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return 0, 0
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else:
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image_border = 32 - (size % 32)
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if (image_border % 2) == 0:
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return round(image_border / 2), round(image_border / 2)
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else:
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return round(image_border / 2), round((image_border / 2) + 1)
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def _print_image(self, line, size):
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""" Print formatted image
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:param line:
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:param size:
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"""
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i = 0
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cont = 0
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pbuffer = ""
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self._raw(S_RASTER_N)
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pbuffer = "%02X%02X%02X%02X" % (((size[0]/size[1])/8), 0, size[1] & 0xff, size[1] >> 8)
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self._raw(binascii.unhexlify(pbuffer))
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pbuffer = ""
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while i < len(line):
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hex_string = int(line[i:i+8], 2)
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pbuffer += "%02X" % hex_string
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i += 8
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cont += 1
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if cont % 4 == 0:
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self._raw(binascii.unhexlify(pbuffer))
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pbuffer = ""
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cont = 0
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def _convert_image(self, im):
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""" Parse image and prepare it to a printable format
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:param im: image data
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:raises: :py:exc:`~escpos.exceptions.ImageSizeError`
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"""
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pixels = []
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pix_line = ""
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im_left = ""
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im_right = ""
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switch = 0
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img_size = [0, 0]
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if im.size[0] > 512:
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print ("WARNING: Image is wider than 512 and could be truncated at print time ")
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if im.size[1] > 0xffff:
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raise ImageSizeError()
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im_border = self._check_image_size(im.size[0])
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for i in range(im_border[0]):
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im_left += "0"
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for i in range(im_border[1]):
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im_right += "0"
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for y in range(im.size[1]):
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img_size[1] += 1
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pix_line += im_left
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img_size[0] += im_border[0]
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for x in range(im.size[0]):
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img_size[0] += 1
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RGB = im.getpixel((x, y))
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im_color = (RGB[0] + RGB[1] + RGB[2])
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im_pattern = "1X0"
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pattern_len = len(im_pattern)
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switch = (switch - 1) * (-1)
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for x in range(pattern_len):
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if im_color <= (255 * 3 / pattern_len * (x+1)):
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if im_pattern[x] == "X":
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pix_line += "%d" % switch
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else:
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pix_line += im_pattern[x]
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break
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elif (255 * 3 / pattern_len * pattern_len) < im_color <= (255 * 3):
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pix_line += im_pattern[-1]
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break
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pix_line += im_right
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img_size[0] += im_border[1]
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self._print_image(pix_line, img_size)
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def image(self, path_img):
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""" Open and print an image file
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Prints an image. The image is automatically adjusted in size in order to print it.
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.. todo:: Seems to be broken. Write test that simply executes function with a dummy printer in order to
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check for bugs like these in the future.
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:param path_img: complete filename and path to image of type `jpg`, `gif`, `png` or `bmp`
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"""
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im_open = Image.open(path_img)
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# Remove the alpha channel on transparent images
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if im_open.mode == 'RGBA':
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im_open.load()
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im = Image.new("RGB", im_open.size, (255, 255, 255))
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im.paste(im_open, mask=im_open.split()[3])
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else:
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im = im_open.convert("RGB")
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# Convert the RGB image in printable image
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self._convert_image(im)
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def fullimage(self, img, max_height=860, width=512, histeq=True, bandsize=255):
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""" Resizes and prints an arbitrarily sized image
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.. todo:: Seems to be broken. Write test that simply executes function with a dummy printer in order to
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check for bugs like these in the future.
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"""
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if isinstance(img, (Image, Image.Image)):
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im = img.convert("RGB")
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else:
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im = Image.open(img).convert("RGB")
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if histeq:
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# Histogram equaliztion
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h = im.histogram()
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lut = []
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for b in range(0, len(h), 256):
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# step size
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step = reduce(operator.add, h[b:b+256]) / 255
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# create equalization lookup table
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n = 0
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for i in range(256):
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lut.append(n / step)
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n = n + h[i+b]
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im = im.point(lut)
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if width:
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ratio = float(width) / im.size[0]
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newheight = int(ratio * im.size[1])
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# Resize the image
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im = im.resize((width, newheight), Image.ANTIALIAS)
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if max_height and im.size[1] > max_height:
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im = im.crop((0, 0, im.size[0], max_height))
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# Divide into bands
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current = 0
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while current < im.size[1]:
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self.image(im.crop((0, current, width or im.size[0],
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min(im.size[1], current + bandsize))))
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current += bandsize
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def direct_image(self, image):
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""" Send image to printer
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:param image:
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"""
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mask = 0x80
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i = 0
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temp = 0
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(width, height) = image.size
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self._raw(S_RASTER_N)
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headerX = int(width / 8)
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headerY = height
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buf = "%02X" % (headerX & 0xff)
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buf += "%02X" % ((headerX >> 8) & 0xff)
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buf += "%02X" % (headerY & 0xff)
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buf += "%02X" % ((headerY >> 8) & 0xff)
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#self._raw(binascii.unhexlify(buf))
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for y in range(height):
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for x in range(width):
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value = image.getpixel((x, y))
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value |= (value << 8)
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if value == 0:
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temp |= mask
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mask >>= 1
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i += 1
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if i == 8:
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buf += ("%02X" % temp)
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mask = 0x80
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i = 0
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temp = 0
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self._raw(binascii.unhexlify(bytes(buf, "ascii")))
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self._raw('\n')
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def qr(self, text):
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""" Print QR Code for the provided string
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Prints a QR-code. The size has been adjusted to version 4, so it is small enough to be
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printed but also big enough to be read by a smartphone.
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:param text: text to generate a QR-Code from
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"""
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qr_code = qrcode.QRCode(version=4, box_size=4, border=1, error_correction=qrcode.constants.ERROR_CORRECT_H)
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qr_code.add_data(text)
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qr_code.make(fit=True)
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qr_img = qr_code.make_image()
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im = qr_img._img.convert("RGB")
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# Convert the RGB image in printable image
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self._convert_image(im)
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def charcode(self, code):
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""" Set Character Code Table
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Sends the control sequence from :py:mod:`escpos.constants` to the printer
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with :py:meth:`escpos.printer.'implementation'._raw()`.
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:param code: Name of CharCode
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:raises: :py:exc:`~escpos.exceptions.CharCodeError`
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"""
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if code.upper() == "USA":
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self._raw(CHARCODE_PC437)
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elif code.upper() == "JIS":
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self._raw(CHARCODE_JIS)
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elif code.upper() == "MULTILINGUAL":
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self._raw(CHARCODE_PC850)
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elif code.upper() == "PORTUGUESE":
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self._raw(CHARCODE_PC860)
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elif code.upper() == "CA_FRENCH":
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self._raw(CHARCODE_PC863)
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elif code.upper() == "NORDIC":
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self._raw(CHARCODE_PC865)
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elif code.upper() == "WEST_EUROPE":
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self._raw(CHARCODE_WEU)
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elif code.upper() == "GREEK":
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self._raw(CHARCODE_GREEK)
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elif code.upper() == "HEBREW":
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self._raw(CHARCODE_HEBREW)
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# elif code.upper() == "LATVIAN": # this is not listed in the constants
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# self._raw(CHARCODE_PC755)
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elif code.upper() == "WPC1252":
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self._raw(CHARCODE_PC1252)
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elif code.upper() == "CIRILLIC2":
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self._raw(CHARCODE_PC866)
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elif code.upper() == "LATIN2":
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self._raw(CHARCODE_PC852)
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elif code.upper() == "EURO":
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self._raw(CHARCODE_PC858)
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elif code.upper() == "THAI42":
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self._raw(CHARCODE_THAI42)
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elif code.upper() == "THAI11":
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self._raw(CHARCODE_THAI11)
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elif code.upper() == "THAI13":
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self._raw(CHARCODE_THAI13)
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elif code.upper() == "THAI14":
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self._raw(CHARCODE_THAI14)
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elif code.upper() == "THAI16":
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self._raw(CHARCODE_THAI16)
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elif code.upper() == "THAI17":
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self._raw(CHARCODE_THAI17)
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elif code.upper() == "THAI18":
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self._raw(CHARCODE_THAI18)
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else:
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raise CharCodeError()
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def barcode(self, code, bc, height=64, width=3, pos="BELOW", font="A", align_ct=True):
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""" Print Barcode
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This method allows to print barcodes. The rendering of the barcode is done by the printer and therefore has to
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be supported by the unit. Currently you have to check manually whether your barcode text is correct. Uncorrect
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barcodes may lead to unexpected printer behaviour.
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.. todo:: Add a method to check barcode codes. Alternatively or as an addition write explanations about each
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barcode-type. Research whether the check digits can be computed autmatically.
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Use the parameters `height` and `width` for adjusting of the barcode size. Please take notice that the barcode
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will not be printed if it is outside of the printable area. (Which should be impossible with this method, so
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this information is probably more useful for debugging purposes.)
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.. todo:: On TM-T88II width from 1 to 6 is accepted. Try to acquire command reference and correct the code.
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.. todo:: Supplying pos does not have an effect for every barcode type. Check and document for which types this
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is true.
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If you do not want to center the barcode you can call the method with `align_ct=False`, which will disable
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automatic centering. Please note that when you use center alignment, then the alignment of text will be changed
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automatically to centered. You have to manually restore the alignment if necessary.
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.. todo:: If further barcode-types are needed they could be rendered transparently as an image. (This could also
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be of help if the printer does not support types that others do.)
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:param code: alphanumeric data to be printed as bar code
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:param bc: barcode format, possible values are:
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* UPC-A
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* UPC-E
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* EAN13
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* EAN8
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* CODE39
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* ITF
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* NW7
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If none is specified, the method raises :py:exc:`~escpos.exceptions.BarcodeTypeError`.
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:param height: barcode height, has to be between 1 and 255
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*default*: 64
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:type height: int
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:param width: barcode width, has to be between 2 and 6
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*default*: 3
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:type width: int
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:param pos: where to place the text relative to the barcode, *default*: BELOW
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* ABOVE
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* BELOW
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* BOTH
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* OFF
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:param font: select font (see ESC/POS-documentation, the device often has two fonts), *default*: A
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* A
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* B
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:param align_ct: If this parameter is True the barcode will be centered. Otherwise no alignment command will be
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issued.
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:type align_ct: bool
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:raises: :py:exc:`~escpos.exceptions.BarcodeSizeError`,
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:py:exc:`~escpos.exceptions.BarcodeTypeError`,
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:py:exc:`~escpos.exceptions.BarcodeCodeError`
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"""
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# Align Bar Code()
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if align_ct:
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self._raw(TXT_ALIGN_CT)
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# Height
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if 1 <= height <= 255:
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self._raw(BARCODE_HEIGHT + chr(height))
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else:
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raise BarcodeSizeError("height = {height}".format(height=height))
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# Width
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if 2 <= width <= 6:
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self._raw(BARCODE_WIDTH + chr(width))
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else:
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raise BarcodeSizeError("width = {width}".format(width=width))
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# Font
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if font.upper() == "B":
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self._raw(BARCODE_FONT_B)
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else: # DEFAULT FONT: A
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self._raw(BARCODE_FONT_A)
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# Position
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if pos.upper() == "OFF":
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self._raw(BARCODE_TXT_OFF)
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elif pos.upper() == "BOTH":
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self._raw(BARCODE_TXT_BTH)
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elif pos.upper() == "ABOVE":
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self._raw(BARCODE_TXT_ABV)
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else: # DEFAULT POSITION: BELOW
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self._raw(BARCODE_TXT_BLW)
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# Type
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if bc.upper() == "UPC-A":
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self._raw(BARCODE_UPC_A)
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elif bc.upper() == "UPC-E":
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self._raw(BARCODE_UPC_E)
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elif bc.upper() == "EAN13":
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self._raw(BARCODE_EAN13)
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elif bc.upper() == "EAN8":
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self._raw(BARCODE_EAN8)
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elif bc.upper() == "CODE39":
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self._raw(BARCODE_CODE39)
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elif bc.upper() == "ITF":
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self._raw(BARCODE_ITF)
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elif bc.upper() in ("NW7", "CODABAR"):
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self._raw(BARCODE_NW7)
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else:
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raise BarcodeTypeError(bc)
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# Print Code
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if code:
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self._raw(code)
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else:
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raise BarcodeCodeError()
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def text(self, txt):
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""" Print alpha-numeric text
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The text has to be encoded in the currently selected codepage.
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:param txt: text to be printed
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:raises: :py:exc:`~escpos.exceptions.TextError`
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"""
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if txt:
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self._raw(txt)
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else:
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# TODO: why is it problematic to print an empty string?
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raise TextError()
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def block_text(self, txt, columns=None):
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""" Text is printed wrapped to specified columns
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:param txt: text to be printed
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:param columns: amount of columns
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:return: None
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"""
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colCount = self.columns if columns is None else columns
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self.text(textwrap.fill(txt, colCount))
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def set(self, align='left', font='a', text_type='normal', width=1, height=1, density=9, invert=False, smooth=False, flip=False):
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""" Set text properties by sending them to the printer
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:param align: horizontal position for text, possible values are:
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* CENTER
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* LEFT
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* RIGHT
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*default*: LEFT
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:param font: font type, possible values are A or B, *default*: A
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:param text_type: text type, possible values are:
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* B for bold
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* U for underlined
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* U2 for underlined, version 2
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* BU for bold and underlined
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* BU2 for bold and underlined, version 2
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* NORMAL for normal text
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*default*: NORMAL
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:param width: text width multiplier, decimal range 1-8, *default*: 1
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:param height: text height multiplier, decimal range 1-8, *default*: 1
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:param density: print density, value from 0-8, if something else is supplied the density remains unchanged
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:param invert: True enables white on black printing, *default*: False
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:param smooth: True enables text smoothing. Effective on 4x4 size text and larger, *default*: False
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:param flip: True enables upside-down printing, *default*: False
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:type invert: bool
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"""
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# Width
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if height == 2 and width == 2:
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self._raw(TXT_NORMAL)
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self._raw(TXT_4SQUARE)
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elif height == 2 and width == 1:
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self._raw(TXT_NORMAL)
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self._raw(TXT_2HEIGHT)
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elif width == 2 and height == 1:
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self._raw(TXT_NORMAL)
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self._raw(TXT_2WIDTH)
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elif width == 1 and height == 1:
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self._raw(TXT_NORMAL)
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elif width >= 1 and width <= 8 and height >= 1 and height <= 8 and isinstance(width, int) and isinstance(height, int):
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self._raw(TXT_SIZE + chr(TXT_WIDTH[width] + TXT_HEIGHT[height]))
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else:
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raise SetVariableError()
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# Upside down
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if flip == True:
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self._raw(TXT_FLIP_ON)
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else:
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self._raw(TXT_FLIP_OFF)
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# Smoothing
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if smooth == True:
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self._raw(TXT_SMOOTH_ON)
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else:
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self._raw(TXT_SMOOTH_OFF)
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# Type
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if text_type.upper() == "B":
|
|
self._raw(TXT_BOLD_ON)
|
|
self._raw(TXT_UNDERL_OFF)
|
|
elif text_type.upper() == "U":
|
|
self._raw(TXT_BOLD_OFF)
|
|
self._raw(TXT_UNDERL_ON)
|
|
elif text_type.upper() == "U2":
|
|
self._raw(TXT_BOLD_OFF)
|
|
self._raw(TXT_UNDERL2_ON)
|
|
elif text_type.upper() == "BU":
|
|
self._raw(TXT_BOLD_ON)
|
|
self._raw(TXT_UNDERL_ON)
|
|
elif text_type.upper() == "BU2":
|
|
self._raw(TXT_BOLD_ON)
|
|
self._raw(TXT_UNDERL2_ON)
|
|
elif text_type.upper == "NORMAL":
|
|
self._raw(TXT_BOLD_OFF)
|
|
self._raw(TXT_UNDERL_OFF)
|
|
# Font
|
|
if font.upper() == "B":
|
|
self._raw(TXT_FONT_B)
|
|
else: # DEFAULT FONT: A
|
|
self._raw(TXT_FONT_A)
|
|
# Align
|
|
if align.upper() == "CENTER":
|
|
self._raw(TXT_ALIGN_CT)
|
|
elif align.upper() == "RIGHT":
|
|
self._raw(TXT_ALIGN_RT)
|
|
elif align.upper() == "LEFT":
|
|
self._raw(TXT_ALIGN_LT)
|
|
# Density
|
|
if density == 0:
|
|
self._raw(PD_N50)
|
|
elif density == 1:
|
|
self._raw(PD_N37)
|
|
elif density == 2:
|
|
self._raw(PD_N25)
|
|
elif density == 3:
|
|
self._raw(PD_N12)
|
|
elif density == 4:
|
|
self._raw(PD_0)
|
|
elif density == 5:
|
|
self._raw(PD_P12)
|
|
elif density == 6:
|
|
self._raw(PD_P25)
|
|
elif density == 7:
|
|
self._raw(PD_P37)
|
|
elif density == 8:
|
|
self._raw(PD_P50)
|
|
else: # DEFAULT: DOES NOTHING
|
|
pass
|
|
# Invert Printing
|
|
if invert:
|
|
self._raw(TXT_INVERT_ON)
|
|
else:
|
|
self._raw(TXT_INVERT_OFF)
|
|
|
|
def cut(self, mode=''):
|
|
""" Cut paper.
|
|
|
|
Without any arguments the paper will be cut completely. With 'mode=PART' a partial cut will
|
|
be attempted. Note however, that not all models can do a partial cut. See the documentation of
|
|
your printer for details.
|
|
.. todo:: Check this function on TM-T88II.
|
|
|
|
:param mode: set to 'PART' for a partial cut
|
|
"""
|
|
# Fix the size between last line and cut
|
|
# TODO: handle this with a line feed
|
|
self._raw("\n\n\n\n\n\n")
|
|
if mode.upper() == "PART":
|
|
self._raw(PAPER_PART_CUT)
|
|
else: # DEFAULT MODE: FULL CUT
|
|
self._raw(PAPER_FULL_CUT)
|
|
|
|
def cashdraw(self, pin):
|
|
""" Send pulse to kick the cash drawer
|
|
|
|
Kick cash drawer on pin 2 or pin 5 according to parameter.
|
|
|
|
:param pin: pin number, 2 or 5
|
|
:raises: :py:exc:`~escpos.exceptions.CashDrawerError`
|
|
"""
|
|
if pin == 2:
|
|
self._raw(CD_KICK_2)
|
|
elif pin == 5:
|
|
self._raw(CD_KICK_5)
|
|
else:
|
|
raise CashDrawerError()
|
|
|
|
def hw(self, hw):
|
|
""" Hardware operations
|
|
|
|
:param hw: hardware action, may be:
|
|
|
|
* INIT
|
|
* SELECT
|
|
* RESET
|
|
"""
|
|
if hw.upper() == "INIT":
|
|
self._raw(HW_INIT)
|
|
elif hw.upper() == "SELECT":
|
|
self._raw(HW_SELECT)
|
|
elif hw.upper() == "RESET":
|
|
self._raw(HW_RESET)
|
|
else: # DEFAULT: DOES NOTHING
|
|
pass
|
|
|
|
def control(self, ctl, pos=4):
|
|
""" Feed control sequences
|
|
|
|
:param ctl: string for the following control sequences:
|
|
|
|
* LF *for Line Feed*
|
|
* FF *for Form Feed*
|
|
* CR *for Carriage Return*
|
|
* HT *for Horizontal Tab*
|
|
* VT *for Vertical Tab*
|
|
|
|
:param pos: integer between 1 and 16, controls the horizontal tab position
|
|
:raises: :py:exc:`~escpos.exceptions.TabPosError`
|
|
"""
|
|
# Set tab positions
|
|
if pos < 1 or pos > 16:
|
|
raise TabPosError()
|
|
else:
|
|
self._raw("".join([CTL_SET_HT, hex(pos)]))
|
|
# Set position
|
|
if ctl.upper() == "LF":
|
|
self._raw(CTL_LF)
|
|
elif ctl.upper() == "FF":
|
|
self._raw(CTL_FF)
|
|
elif ctl.upper() == "CR":
|
|
self._raw(CTL_CR)
|
|
elif ctl.upper() == "HT":
|
|
self._raw(CTL_HT)
|
|
elif ctl.upper() == "VT":
|
|
self._raw(CTL_VT)
|