#!/usr/bin/python
#--------------------------------------
# ___ ___ _ ____
# / _ \/ _ \(_) __/__ __ __
# / , _/ ___/ /\ \/ _ \/ // /
# /_/|_/_/ /_/___/ .__/\_, /
#
/_/ /___/
#
# lcd_16x2.py
# 16x2 LCD Test Script
#
# Author : Matt Hawkins
# Date : 06/04/2015
#
# http://www.raspberrypi-spy.co.uk/
#
#--------------------------------------
# The wiring for the LCD is as follows:
# 1 : GND
# 2 : 5V
# 3 : Contrast (0-5V)*
# 4 : RS (Register Select)
# 5 : R/W (Read Write)
- GROUND THIS PIN
# 6 : Enable or Strobe
# 7 : Data Bit
0
- NOT USED
# 8 : Data Bit
1
- NOT USED
# 9 : Data Bit
2
- NOT USED
# 10: Data Bit
3
- NOT USED
# 11: Data Bit 4
# 12: Data Bit 5
# 13: Data Bit 6
# 14: Data Bit 7
# 15: LCD Backlight +5V**
# 16: LCD Backlight GND
#import
#import RPi.gpio.as GPIO
from pyA20.gpio import gpio
from pyA20.gpio import port
import time
# Define gpio.to LCD mapping
# for RaspberryPi
#LCD_RS = 7
#LCD_E = 8
#LCD_D4 = 25
#LCD_D5 = 24
#LCD_D6 = 23
#LCD_D7 = 18
# for OrangePi
LCD_RS = port.PA21
LCD_E = port.PC3
LCD_D4 = port.PA2
LCD_D5 = port.PC7
LCD_D6 = port.PC4
LCD_D7 = port.PD14
# Define some device constants
LCD_WIDTH = 16 # Maximum characters per
line
LCD_CHR = True
LCD_CMD = False
LCD_LINE_1 = 0x80 # LCD RAM address for the 1st line
LCD_LINE_2 = 0xC0 # LCD RAM address for the 2nd line
# Timing constants
E_PULSE = 0.0005
E_DELAY = 0.0005
def main():
# Main program block
# gpio.setwarnings(False)
gpio.init()
# Use BCM gpio.numbers
gpio.setcfg(LCD_E, gpio.OUTPUT) # E
gpio.setcfg(LCD_RS, gpio.OUTPUT) # RS
gpio.setcfg(LCD_D4, gpio.OUTPUT) # DB4
gpio.setcfg(LCD_D5, gpio.OUTPUT) # DB5
gpio.setcfg(LCD_D6, gpio.OUTPUT) # DB6
gpio.setcfg(LCD_D7, gpio.OUTPUT) # DB7
# Initialise display
lcd_init()
while True:
# Send some test
lcd_string("Rasbperry Pi",LCD_LINE_1)
lcd_string("16x2 LCD Test",LCD_LINE_2)
time.sleep(3) # 3 second delay
# Send some text
lcd_string("1234567890123456",LCD_LINE_1)
lcd_string("abcdefghijklmnop",LCD_LINE_2)
time.sleep(3) # 3 second delay
# Send some text
lcd_string("RaspberryPi-spy",LCD_LINE_1)
lcd_string(".co.uk",LCD_LINE_2)
time.sleep(3)
# Send some text
lcd_string("Follow me on",LCD_LINE_1)
lcd_string("Twitter
@RPiSpy",LCD_LINE_2)
time.sleep(3)
def lcd_init():
# Initialise display
lcd_byte(0x33,LCD_CMD) # 110011 Initialise
lcd_byte(0x32,LCD_CMD) # 110010 Initialise
lcd_byte(0x06,LCD_CMD) # 000110 Cursor move
direction
lcd_byte(0x0C,LCD_CMD) # 001100 Display On,Cursor
Off, Blink Off
lcd_byte(0x28,LCD_CMD) # 101000 Data length, number
of lines, font size
lcd_byte(0x01,LCD_CMD) # 000001 Clear display
time.sleep(E_DELAY)
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
# High bits
gpio.output(LCD_D4, False)
gpio.output(LCD_D5, False)
gpio.output(LCD_D6, False)
gpio.output(LCD_D7, False)
if bits&0x10==0x10:
gpio.output(LCD_D4, True)
if bits&0x20==0x20:
gpio.output(LCD_D5, True)
if bits&0x40==0x40:
gpio.output(LCD_D6, True)
if bits&0x80==0x80:
gpio.output(LCD_D7, True)
# Toggle 'Enable' pin
lcd_toggle_enable()
# Low bits
gpio.output(LCD_D4, False)
gpio.output(LCD_D5, False)
gpio.output(LCD_D6, False)
gpio.output(LCD_D7, False)
if bits&0x01==0x01:
gpio.output(LCD_D4, True)
if bits&0x02==0x02:
gpio.output(LCD_D5, True)
if bits&0x04==0x04:
gpio.output(LCD_D6, True)
if bits&0x08==0x08:
gpio.output(LCD_D7, True)
# Toggle 'Enable' pin
lcd_toggle_enable()
def lcd_toggle_enable():
# Toggle enable
time.sleep(E_DELAY)
gpio.output(LCD_E, True)
time.sleep(E_PULSE)
gpio.output(LCD_E, False)
time.sleep(E_DELAY)
def lcd_string(message,line):
# Send string to display
message = message.ljust(LCD_WIDTH," ")
lcd_byte(line, LCD_CMD)
for i in range(LCD_WIDTH):
lcd_byte(ord(message[i]),LCD_CHR)
if __name__ == '__main__':
try:
main()
except KeyboardInterrupt:
pass
finally:
lcd_byte(0x01, LCD_CMD)
lcd_string("Goodbye!",LCD_LINE_1)
# gpio.cleanup() |