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Raspberry Pi hd44780 with i2c LCD displaying performance

This is the final product:

The display will show the status of the raid array, and will show the current percentage load of the CPU and the memory.

Raspberry Pi showing performance statistics

First follow either of these guides:

This will go over the needed libraries ( and

The below script can be placed in /bin/ and scheduled in crontab using crontab -e and then adding the line @reboot python3 /bin/ &

This will automatically start the script after reboot.

This is the script to display the stats:

import lcddriver
from time import *
lcd = lcddriver.lcd()
import subprocess
import psutil

# This script will display the status of the raid array, in use memory and CPU load on the lcd screen.
# The LCD has two lines, so the script will display the raid status on the first line and the memory and CPU load on the second line. 
# The script will run in an infinite loop, updating the status every 60 seconds. 
# The script will use the mdadm command to get the raid status and psutil to get the memory and CPU load. 

while True:
    output = subprocess.check_output(['mdadm', '-D', '/dev/md0'])
    output = output.decode('utf-8').split("\n")
    # get the line that has the state:
    for line in output:
        if "State :" in line:
            state = line.strip()
    mem = psutil.virtual_memory()
    lcd.lcd_display_string(state, 1)
    lcd.lcd_display_string("Mem:" + str(int(mem.percent)) + "% CPU:" + str(int(psutil.cpu_percent())) + "%", 2)

The full project is also available on Github. The needed libraries that work with this code are included.