The following code can be downloaded to your raspberry pi and run to get the date, time and IP address of your machine on the LCD display.
from subprocess import Popen, PIPE
from time import sleep
from datetime import datetime
import board
import digitalio
import adafruit_character_lcd.character_lcd as characterlcd
# Modify this if you have a different sized character LCD
lcd_columns = 16
lcd_rows = 2
# compatible with all versions of RPI as of Jan. 2019
# v1 - v3B+
lcd_rs = digitalio.DigitalInOut(board.D22)
lcd_en = digitalio.DigitalInOut(board.D17)
lcd_d4 = digitalio.DigitalInOut(board.D25)
lcd_d5 = digitalio.DigitalInOut(board.D24)
lcd_d6 = digitalio.DigitalInOut(board.D23)
lcd_d7 = digitalio.DigitalInOut(board.D18)
# Initialise the lcd class
lcd = characterlcd.Character_LCD_Mono(lcd_rs, lcd_en, lcd_d4, lcd_d5, lcd_d6,
lcd_d7, lcd_columns, lcd_rows)
# looking for an active Ethernet or WiFi device
def find_interface():
find_device = "ip addr show"
interface_parse = run_cmd(find_device)
for line in interface_parse.splitlines():
if "state UP" in line:
dev_name = line.split(':')[1]
return dev_name
# find an active IP on the first LIVE network device
def parse_ip():
find_ip = "ip addr show %s" % interface
find_ip = "ip addr show %s" % interface
ip_parse = run_cmd(find_ip)
for line in ip_parse.splitlines():
if "inet " in line:
ip = line.split(' ')[5]
ip = ip.split('/')[0]
return ip
# run unix shell command, return as ASCII
def run_cmd(cmd):
p = Popen(cmd, shell=True, stdout=PIPE)
output = p.communicate()[0]
return output.decode('ascii')
# wipe LCD screen before we start
lcd.clear()
# before we start the main loop - detect active network device and ip address
sleep(2)
interface = find_interface()
ip_address = parse_ip()
while True:
# date and time
lcd_line_1 = datetime.now().strftime('%b %d %H:%M:%S\n')
# current ip address
lcd_line_2 = "IP " + ip_address
# combine both lines into one update to the display
lcd.message = lcd_line_1 + lcd_line_2
sleep(2)
Let's put this file right in your home directory for simplicity. The wget command makes things easy.
Download:
file
$ wget https://raw.githubusercontent.com/adafruit/Adafruit_Learning_System_Guides/master/Drive_a_16x2_LCD_with_the_Raspberry_Pi/Drive_a_16x2_LCD_with_the_Raspberry_Pi.py
The following command will start the program and you should see the LCD display come to life with date, time and IP address.
Download:
file
$ sudo python3 ./Drive_a_16x2_LCD_with_the_Raspberry_Pi.py
