LCD-Display ST7066

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import Adafruit_BBIO.GPIO as GPIO

import time

# Define GPIO to LCD mapping

LCD_RS="P9_15"

LCD_E="P9_16"

LCD_D4="P9_21"

LCD_D5="P9_22"

LCD_D6="P9_23"

LCD_D7="P9_24"

OUT=GPIO.OUT

LOW=GPIO.LOW

HIGH=GPIO.HIGH

# Define some device constants

LCD_WIDTH = 16    # Maximum characters per line

LCD_CHR = True

LCD_CMD = False

LCD_LINE_1 = 0x00 # LCD RAM address for the 1st line

LCD_LINE_2 = 0x28 # LCD RAM address for the 2nd line

# Timing constants

E_PULSE = 0.00005 

E_DELAY = 0.00005

def main():  # Main program block

  GPIO.setup(LCD_E,OUT)  # E

  GPIO.setup(LCD_RS,OUT) # RS

  GPIO.setup(LCD_D4,OUT) # DB4

  GPIO.setup(LCD_D5,OUT) # DB5

  GPIO.setup(LCD_D6,OUT) # DB6

  GPIO.setup(LCD_D7,OUT) # DB7

  # Initialise display

  lcd_init()

def lcd_init():

  # Initialise display

  lcd_byte(0x30,LCD_CMD) # 110011 Initialise

  time.sleep(0.01)

  lcd_byte(0x30,LCD_CMD) # 110010 Initialise

  time.sleep(0.01)

  lcd_byte(0x30,LCD_CMD) # 000110 Cursor move direction

  time.sleep(0.01)

  lcd_byte(0x20,LCD_CMD) # 001100 Display On,Cursor Off, Blink Off

  time.sleep(0.01)

  #lcd_byte(0x1C,LCD_CMD) # 101000 Data length, number of lines, font size

  #  time.sleep(0.01)

  lcd_byte(0x0C,LCD_CMD)

  time.sleep(0.01)

  lcd_byte(0x01,LCD_CMD)

  time.sleep(0.01)

  #lcd_byte(0x06,LCD_CMD) # 000001 Clear display

def lcd_byte(bits, mode):

  # Send byte to data pins

  # bits = data

  # mode = True  for character

  #       False for command

  GPIO.output(LCD_RS, mode) # RS

  GPIO.output(LCD_D4, False)     # High bits

  GPIO.output(LCD_D5, False)

  GPIO.output(LCD_D6, False)

  GPIO.output(LCD_D7, False)

  time.sleep(0.001)

  lcd_toggle_enable()

  if bits&0x10:

    GPIO.output(LCD_D4, True)

  if bits&0x20:

    GPIO.output(LCD_D5, True)

  if bits&0x40:   GPIO.output(LCD_D6, True)

  if bits&0x80:

    GPIO.output(LCD_D7, True)

  time.sleep(E_PULSE)

  GPIO.output(LCD_E, True)

  time.sleep(E_DELAY)

  GPIO.output(LCD_E, False)

  time.sleep(E_PULSE)

# lcd_toggle_enable()

  GPIO.output(LCD_D4, False)

  GPIO.output(LCD_D5, False)

  GPIO.output(LCD_D6, False)

  GPIO.output(LCD_D7, False)

  if bits&0x01:

    GPIO.output(LCD_D4, True)

  if bits&0x02:

    GPIO.output(LCD_D5, True)

  if bits&0x04:

    GPIO.output(LCD_D6, True)

  if bits&0x08:

    GPIO.output(LCD_D7, True)

  lcd_toggle_enable()

def lcd_toggle_enable():

  time.sleep(0.005)

  GPIO.output(LCD_E, False)

  time.sleep(E_PULSE)

  GPIO.output(LCD_E, True)

  time.sleep(E_DELAY)

  GPIO.output(LCD_E, False)

  time.sleep(0.005)

def lcd_string(zeile,text):

  if zeile == 1:

      lcd_byte(LCD_LINE_1, LCD_CMD) 

  if zeile == 2:

      lcd_byte(LCD_LINE_1, LCD_CMD)

  message=text.ljust(LCD_WIDTH,'_')

  for i in range(LCD_WIDTH):      

    lcd_byte(ord(message[i]),LCD_CHR)

    main()

lcd_string(1,'abc')

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