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This article is about how raspberry pie uses Python to implement i2C. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

First of all, raspberry pie has to install python-smbus, i2c-tools.

Then modify the file: sudo nano / etc/modules, add the lines i2c-bcm2708 and i2c-dev, and Raspbian needs to activate i2c in raspi-config.

Check the device address with sudo i2cdetect-y 1

Example 1:LCD2004, device address is 0x27

First write a driver caller i2c_driver_lcd.py

Import smbusfrom time import * # LCD AddressADDRESS = 0x27# commandsLCD_CLEARDISPLAY = 0x01LCD_RETURNHOME = 0x02LCD_ENTRYMODESET = 0x04LCD_DISPLAYCONTROL = 0x08LCD_CURSORSHIFT = 0x10LCD_FUNCTIONSET = 0x20LCD_SETCGRAMADDR = 0x40LCD_SETDDRAMADDR = 0x80# flags for display entry modeLCD_ENTRYRIGHT = 0x00LCD_ENTRYLEFT = 0x02LCD_ENTRYSHIFTINCREMENT = 0x01LCD_ENTRYSHIFTDECREMENT = 0x00# flags for display on/off controlLCD_DISPLAYON = 0x04LCD_DISPLAYOFF = 0x00LCD_CURSORON = 0x02LCD_CURSOROFF = 0x00LCD_BLINKON = 0x01LCD_BLINKOFF = 0x00# flags for display/cursor shiftLCD_DISPLAYMOVE = 0x08LCD_CURSORMOVE = 0x00LCD_MOVERIGHT = 0x04LCD_MOVELEFT = 0x00# flags for function setLCD_8BITMODE = 0x10LCD_4BITMODE = 0x00LCD_2LINE = 0x08LCD_1LINE = 0x00LCD_5x10DOTS = 0x04LCD_5x8DOTS = 0x00# flags for backlight controlLCD_BACKLIGHT = 0x08LCD_NOBACKLIGHT = 0x00# set init LCD BACKLIGHT ON or OFFdef lcd_backlight (lcdbl=1): if lcdbl= = 0: return LCD_NOBACKLIGHT return LCD_BACKLIGHTEn = 0b00000100 # Enable bitRw = 0b00000010 # Read/Write bitRs = 0b00000001 # Register select bitclass lcd (object): # initializes objects and lcd def _ init__ (self Lcd_bl Port=1): self.addr = ADDRESS self.bus = smbus.SMBus (port) self.lcd_bl = lcd_bl self.lcd_write (0x03) self.lcd_write (0x02) self.lcd_write (LCD_FUNCTIONSET | LCD_2LINE | LCD_5x8DOTS | LCD_4BITMODE) Self.lcd_write (LCD_DISPLAYCONTROL | LCD_DISPLAYON) self.lcd_write (LCD_CLEARDISPLAY) self.lcd_write (LCD_ENTRYMODESET | LCD_ENTRYLEFT) sleep (0.2) def set_lcd (self Set_lcdbl): self.lcd_bl = set_lcdbl # clocks EN to latch command def lcd_strobe (self, data): self.write_cmd (data | En | lcd_backlight (self.lcd_bl)) sleep (.0005) self.write_cmd (data & ~ En) | lcd_backlight (self.lcd_bl)) sleep (.0001) def lcd_write_four_bits (self Data): self.write_cmd (data | lcd_backlight (self.lcd_bl)) self.lcd_strobe (data) # write a command to lcd def lcd_write (self, cmd, mode=0): self.lcd_write_four_bits (mode | (cmd & 0xF0)) self.lcd_write_four_bits (mode | (cmd)

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