LCD via i2c

i2c_lib.py

@@ -0,0 +1,35 @@
+import smbus
+from time import *
+
+class i2c_device:
+   def __init__(self, addr, port=1):
+      self.addr = addr
+      self.bus = smbus.SMBus(port)
+
+# Write a single command
+   def write_cmd(self, cmd):
+      self.bus.write_byte(self.addr, cmd)
+      sleep(0.0001)
+
+# Write a command and argument
+   def write_cmd_arg(self, cmd, data):
+      self.bus.write_byte_data(self.addr, cmd, data)
+      sleep(0.0001)
+
+# Write a block of data
+   def write_block_data(self, cmd, data):
+      self.bus.write_block_data(self.addr, cmd, data)
+      sleep(0.0001)
+
+# Read a single byte
+   def read(self):
+      return self.bus.read_byte(self.addr)
+
+# Read
+   def read_data(self, cmd):
+      return self.bus.read_byte_data(self.addr, cmd)
+
+# Read a block of data
+   def read_block_data(self, cmd):
+      return self.bus.read_block_data(self.addr, cmd)
+

lcd.py

@@ -1,27 +1,10 @@
-from subprocess import Popen, PIPE
-from time import sleep, perf_counter
-from datetime import datetime
-import board
-import digitalio
-import adafruit_character_lcd.character_lcd as characterlcd
+import lcddriver
+from time import *
 
+lcd = lcddriver.lcd()
 
-lcd_columns = 16
-lcd_rows = 2
+lcd.lcd_display_string("Freya, Robert", 1)
+lcd.lcd_display_string("und Elisabeth Clara", 2)
+lcd.lcd_display_string("05.05.2024 20:18", 3)
+lcd.lcd_display_string("================", 4)
 
-lcd_rs = digitalio.DigitalInOut(board.D16)
-lcd_en = digitalio.DigitalInOut(board.D17)
-lcd_d4 = digitalio.DigitalInOut(board.D13)
-lcd_d5 = digitalio.DigitalInOut(board.D6)
-lcd_d6 = digitalio.DigitalInOut(board.D5)
-lcd_d7 = digitalio.DigitalInOut(board.D26)
-
-
-lcd = characterlcd.Character_LCD_Mono(lcd_rs, lcd_en, lcd_d4, lcd_d5, lcd_d6,
-                                      lcd_d7, lcd_columns, lcd_rows)
-
-lcd.clear()
-
-
-def write(row1, row2):
-    lcd.message = row1.ljust(16)[:16] + "\n" + row2.ljust(16)[:16]

lcddriver.py

@@ -0,0 +1,103 @@
+import i2c_lib
+from time import *
+
+# LCD Address
+ADDRESS = 0x27
+
+# commands
+LCD_CLEARDISPLAY = 0x01
+LCD_RETURNHOME = 0x02
+LCD_ENTRYMODESET = 0x04
+LCD_DISPLAYCONTROL = 0x08
+LCD_CURSORSHIFT = 0x10
+LCD_FUNCTIONSET = 0x20
+LCD_SETCGRAMADDR = 0x40
+LCD_SETDDRAMADDR = 0x80
+
+# flags for display entry mode
+LCD_ENTRYRIGHT = 0x00
+LCD_ENTRYLEFT = 0x02
+LCD_ENTRYSHIFTINCREMENT = 0x01
+LCD_ENTRYSHIFTDECREMENT = 0x00
+
+# flags for display on/off control
+LCD_DISPLAYON = 0x04
+LCD_DISPLAYOFF = 0x00
+LCD_CURSORON = 0x02
+LCD_CURSOROFF = 0x00
+LCD_BLINKON = 0x01
+LCD_BLINKOFF = 0x00
+
+# flags for display/cursor shift
+LCD_DISPLAYMOVE = 0x08
+LCD_CURSORMOVE = 0x00
+LCD_MOVERIGHT = 0x04
+LCD_MOVELEFT = 0x00
+
+# flags for function set
+LCD_8BITMODE = 0x10
+LCD_4BITMODE = 0x00
+LCD_2LINE = 0x08
+LCD_1LINE = 0x00
+LCD_5x10DOTS = 0x04
+LCD_5x8DOTS = 0x00
+
+# flags for backlight control
+LCD_BACKLIGHT = 0x08
+LCD_NOBACKLIGHT = 0x00
+
+En = 0b00000100 # Enable bit
+Rw = 0b00000010 # Read/Write bit
+Rs = 0b00000001 # Register select bit
+
+class lcd:
+   #initializes objects and lcd
+   def __init__(self):
+      self.lcd_device = i2c_lib.i2c_device(ADDRESS)
+
+      self.lcd_write(0x03)
+      self.lcd_write(0x03)
+      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)
+
+   # clocks EN to latch command
+   def lcd_strobe(self, data):
+      self.lcd_device.write_cmd(data | En | LCD_BACKLIGHT)
+      sleep(.0005)
+      self.lcd_device.write_cmd(((data & ~En) | LCD_BACKLIGHT))
+      sleep(.0001)
+
+   def lcd_write_four_bits(self, data):
+      self.lcd_device.write_cmd(data | LCD_BACKLIGHT)
+      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 << 4) & 0xF0))
+
+   # put string function
+   def lcd_display_string(self, string, line):
+      if line == 1:
+         self.lcd_write(0x80)
+      if line == 2:
+         self.lcd_write(0xC0)
+      if line == 3:
+         self.lcd_write(0x94)
+      if line == 4:
+         self.lcd_write(0xD4)
+
+      for char in string:
+         self.lcd_write(ord(char), Rs)
+
+   # clear lcd and set to home
+   def lcd_clear(self):
+      self.lcd_write(LCD_CLEARDISPLAY)
+      self.lcd_write(LCD_RETURNHOME)
+