1602

sudo apt-get install i2c-tools python-smbus

sudo i2cdetect -y 1

#!/usr/bin/python

import time

import smbus

import socket

def get_host_ip():

try:

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

s.connect(('8.8.8.8', 80))

ip = s.getsockname()[0]

finally:

s.close()

return ip

BUS = smbus.SMBus(1)

#LCD_ADDR = 0x27

LCD_ADDR = 0x3F # sudo i2cdetect -y -a 0

def send_command(comm):

# Send bit7-4 firstly

buf = comm & 0xF0

buf |= 0x04              # RS = 0, RW = 0, EN = 1

BUS.write_byte(LCD_ADDR ,buf)

time.sleep(0.002)

buf &= 0xFB              # Make EN = 0

BUS.write_byte(LCD_ADDR ,buf)

# Send bit3-0 secondly

buf = (comm & 0x0F) << 4

buf |= 0x04              # RS = 0, RW = 0, EN = 1

BUS.write_byte(LCD_ADDR ,buf)

time.sleep(0.002)

buf &= 0xFB              # Make EN = 0

BUS.write_byte(LCD_ADDR ,buf)

def send_data(data):

# Send bit7-4 firstly

buf = data & 0xF0

buf |= 0x05              # RS = 1, RW = 0, EN = 1

BUS.write_byte(LCD_ADDR ,buf)

time.sleep(0.002)

buf &= 0xFB              # Make EN = 0

BUS.write_byte(LCD_ADDR ,buf)

# Send bit3-0 secondly

buf = (data & 0x0F) << 4

buf |= 0x05              # RS = 1, RW = 0, EN = 1

BUS.write_byte(LCD_ADDR ,buf)

time.sleep(0.002)

buf &= 0xFB              # Make EN = 0

BUS.write_byte(LCD_ADDR ,buf)

BUS.write_byte(LCD_ADDR,~0x00) # blacklight on

def init_lcd():

try:

send_command(0x33) # Must initialize to 8-line mode at first

time.sleep(0.005)

send_command(0x32) # Then initialize to 4-line mode

time.sleep(0.005)

send_command(0x28) # 2 Lines & 5*7 dots

time.sleep(0.005)

send_command(0x0C) # Enable display without cursor

time.sleep(0.005)

send_command(0x01) # Clear Screen

except:

return False

else:

return True

def clear_lcd():

send_command(0x01) # Clear Screen

def print_lcd(x, y, str):

if x < 0:

x = 0

if x > 15:

x = 15

if y <0:

y = 0

if y > 1:

y = 1

# Move cursor

addr = 0x80 + 0x40 * y + x

send_command(addr)

for chr in str:

send_data(ord(chr))

if __name__ == '__main__':

init_lcd()

localIP=get_host_ip()

while True:

print_lcd(0, 0,localIP )

file = open("/sys/class/thermal/thermal_zone0/temp")

temp = float(file.read()) / 1000

file.close()

wd="CPU temp : %.1f" %temp

print_lcd(0, 1, wd)

time.sleep(3)

然后是开机自动启动

chmod u+x /etc/rc.local

nano /etc/rc.local

添加

nohup /usr/bin/python /home/pi/1602/show.py