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@cocomoff
Created May 13, 2018
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I2C display for RPI 2 (model B+)
# -*- coding: utf-8 -*-
# original soruce: https://terutakke.com/diary/1602-i2c-serial-lcd-modul/
from time import sleep
from time import gmtime, strftime
import RPi.GPIO as GPIO
import datetime
import smbus
# I/F https://github.com/szazo/DHT11_Python
import dht11
#initialize GPIO
GPIO.setwarnings(False)
GPIO.setmode(GPIO.BCM)
GPIO.cleanup()
#read data using pin4
instance = dht11.DHT11(pin=4)
# Define some device parameters
I2C_ADDR = 0x3f # I2C device address #アドレスが違う場合もあるかもしれない
LCD_WIDTH = 16 # Maximum characters per line
# Define some device constants
LCD_CHR = 1 # Mode - Sending data
LCD_CMD = 0 # Mode - Sending command
LCD_LINE_1 = 0x80 # LCD RAM address for the 1st line
LCD_LINE_2 = 0xC0 # LCD RAM address for the 2nd line
LCD_BACKLIGHT = 0x08 # On
# LCD_BACKLIGHT = 0x00 # Off
ENABLE = 0b00000100 # Enable bit
# Timing constants
E_PULSE = 0.0005
E_DELAY = 0.0005
#Open I2C interface
# bus = smbus.SMBus(0) # Rev 1 Pi uses 0
bus = smbus.SMBus(1) # Rev 2 Pi uses 1
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
sleep(E_DELAY)
def lcd_byte(bits, mode):
# Send byte to data pins
# bits = the data
# mode = 1 for data
# 0 for command
bits_high = mode | (bits & 0xF0) | LCD_BACKLIGHT
bits_low = mode | ((bits<<4) & 0xF0) | LCD_BACKLIGHT
# High bits
bus.write_byte(I2C_ADDR, bits_high)
lcd_toggle_enable(bits_high)
# Low bits
bus.write_byte(I2C_ADDR, bits_low)
lcd_toggle_enable(bits_low)
def lcd_toggle_enable(bits):
# Toggle enable
sleep(E_DELAY)
bus.write_byte(I2C_ADDR,(bits | ENABLE))
sleep(E_PULSE)
bus.write_byte(I2C_ADDR,(bits & ~ENABLE))
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)
def main(): #「日時」を表示
# Main program block
# Initialise display
lcd_init()
while True:
local_time = datetime.datetime.now()
str1 = strftime("%Y.%m.%d (%a)", gmtime())
str2 = local_time.strftime("%H:%M")
lcd_string(str1, LCD_LINE_1)
lcd_string(str2, LCD_LINE_2)
sleep(1)
local_time = datetime.datetime.now()
lcd_string(strftime("%Y.%m.%d (%a)", gmtime()) , LCD_LINE_1)
lcd_string(local_time.strftime("%H %M"), LCD_LINE_2)
sleep(1)
try:
print('Start:' + str(datetime.datetime.now()))
main()
except KeyboardInterrupt:
pass
finally:
LCD_BACKLIGHT = 0x00 #バックライトオフ
lcd_byte(0x01, LCD_CMD) #表示内容クリア
GPIO.cleanup()
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