system monitor for a 4line lcd

displaytest.py

#!/usr/bin/python
import time
from subprocess import *
import RPi.GPIO as GPIO
GPIO.setwarnings(False)

# Zuordnung der GPIO Pins (ggf. anpassen)
DISPLAY_RS = 7
DISPLAY_E  = 8
DISPLAY_DATA4 = 25 
DISPLAY_DATA5 = 24
DISPLAY_DATA6 = 23
DISPLAY_DATA7 = 18




DISPLAY_WIDTH = 20 	# Zeichen je Zeile
DISPLAY_LINE_1 = 0x80 	# Adresse der ersten Display Zeile
DISPLAY_LINE_2 = 0xC0 	# Adresse der zweiten Display Zeile
DISPLAY_LINE_3 = 0x94 	# Adresse der ersten Display Zeile
DISPLAY_LINE_4 = 0xD4 	# Adresse der zweiten Display Zeile
# (bei 4x20-Displays lauten die Adressen der dritten und vierten Zeile: 0x94 und 0xD4)

DISPLAY_CHR = True
DISPLAY_CMD = False
E_PULSE = 0.0005
E_DELAY = 0.0005

def main():
	GPIO.setmode(GPIO.BCM)
	GPIO.setup(DISPLAY_E, GPIO.OUT)
	GPIO.setup(DISPLAY_RS, GPIO.OUT)
	GPIO.setup(DISPLAY_DATA4, GPIO.OUT)
	GPIO.setup(DISPLAY_DATA5, GPIO.OUT)
	GPIO.setup(DISPLAY_DATA6, GPIO.OUT)
	GPIO.setup(DISPLAY_DATA7, GPIO.OUT)

	display_init()

	

	i = 0
	thrd_line = frth_line = ''
	ip = get_ip()
	while True:
		lcd_byte(DISPLAY_LINE_1, DISPLAY_CMD)
		lcd_string('disk:' + get_disk_use() + ' cpu:' + get_cpu_use())
		lcd_byte(DISPLAY_LINE_2, DISPLAY_CMD)
		lcd_string('mem:' + get_mem_use())
		lcd_byte(DISPLAY_LINE_3, DISPLAY_CMD)
		lcd_string(thrd_line)
		lcd_byte(DISPLAY_LINE_4, DISPLAY_CMD)
		lcd_string(frth_line)

		time.sleep(5)
		i += 1
		thrd_line = ip if i%2 == 0 else get_uptime()
		frth_line = get_net_use() if i%2 == 0 else time.strftime("%d.%m.%Y %H:%M")






def display_init():
	lcd_byte(0x33,DISPLAY_CMD)
	lcd_byte(0x32,DISPLAY_CMD)
	lcd_byte(0x28,DISPLAY_CMD)
	lcd_byte(0x0C,DISPLAY_CMD)  
	lcd_byte(0x06,DISPLAY_CMD)
	lcd_byte(0x01,DISPLAY_CMD)  

def lcd_string(message):
	message = message.ljust(DISPLAY_WIDTH," ")  
	for i in range(DISPLAY_WIDTH):
	  lcd_byte(ord(message[i]),DISPLAY_CHR)

def lcd_byte(bits, mode):
	GPIO.output(DISPLAY_RS, mode)
	GPIO.output(DISPLAY_DATA4, False)
	GPIO.output(DISPLAY_DATA5, False)
	GPIO.output(DISPLAY_DATA6, False)
	GPIO.output(DISPLAY_DATA7, False)
	if bits&0x10==0x10:
	  GPIO.output(DISPLAY_DATA4, True)
	if bits&0x20==0x20:
	  GPIO.output(DISPLAY_DATA5, True)
	if bits&0x40==0x40:
	  GPIO.output(DISPLAY_DATA6, True)
	if bits&0x80==0x80:
	  GPIO.output(DISPLAY_DATA7, True)
	time.sleep(E_DELAY)    
	GPIO.output(DISPLAY_E, True)  
	time.sleep(E_PULSE)
	GPIO.output(DISPLAY_E, False)  
	time.sleep(E_DELAY)      
	GPIO.output(DISPLAY_DATA4, False)
	GPIO.output(DISPLAY_DATA5, False)
	GPIO.output(DISPLAY_DATA6, False)
	GPIO.output(DISPLAY_DATA7, False)
	if bits&0x01==0x01:
	  GPIO.output(DISPLAY_DATA4, True)
	if bits&0x02==0x02:
	  GPIO.output(DISPLAY_DATA5, True)
	if bits&0x04==0x04:
	  GPIO.output(DISPLAY_DATA6, True)
	if bits&0x08==0x08:
	  GPIO.output(DISPLAY_DATA7, True)
	time.sleep(E_DELAY)    
	GPIO.output(DISPLAY_E, True)  
	time.sleep(E_PULSE)
	GPIO.output(DISPLAY_E, False)  
	time.sleep(E_DELAY)   
def get_disk_use():
	output = check_output(['df', '-h', '/var/www/html']).split()[11]
	#print output
	return output

def get_net_use():
	output = check_output(['cat', '/proc/net/dev']).split()
	output = 'in:' + str("{:.2f}".format(float(output[21])*.0000000001)) + 'GB out:' + str("{:.2f}".format(float(output[29])*.0000000001)) + 'GB'
	#print output
	return output

def get_mem_use():
	output = check_output(['cat', '/proc/meminfo']).split()
	output = str("{:.0f}".format(float(output[4])*.001)) + 'MB of ' + str("{:.0f}".format(float(output[1])*.001)) + 'MB'
	#print output
	return output

def get_cpu_use():
	output = check_output(['ps', '-eo' , 'pcpu']).split()
	output.pop(0)
	nr = 0

	for x in output:
		nr += float(x)
	
	output = str("{:.2f}".format(nr)) + '%'
	#print output
	return output

def get_ip():
	output = check_output(['ifconfig', 'wlan0']).split()[6]
	output = 'ip:' + output[5:len(output)]
	#print output
	return output

def get_uptime():
	output = check_output(['uptime', '-p'])
	#print output
	return output

if __name__ == '__main__':
	main()