Python Forum

Hello,

I know very little about Python programming, so be gentle with me please

I have a script for detecting a PIR movement on a Raspberry Pi 3b.

from gpiozero import MotionSensor
import os
import RPi.GPIO as GPIO
import time
pir = MotionSensor(21)
while True:
        pir.wait_for_motion()
        print("You moved")
        pir.wait_for_no_motion()

I want to turn a monitor on with the command 'DISPLAY=:0.0 xrandr --output HDMI-1 --auto --rotate left' if movement is detected and off with the command 'DISPLAY=:0.0 xrandr --output HDMI-1 --off' after, say, 5 minutes.

I would be grateful if anyone can tell me how to run these commands from within a Python script

Thanks in advance

"I want to turn a monitor on with the command"

If you mean enter it on the command line, use subprocess.run

That is the command line that I want to run from within a python script

(Mar-24-2025, 08:49 AM)lif Wrote: [ -> ]if movement is detected and off with the command 'DISPLAY=:0.0 xrandr --output HDMI-1 --off' after, say, 5 minutes.

As mention use subprocess and is better to use eg schedule when you need to wait 5-min.

import schedule
import time
import subprocess
from gpiozero import MotionSensor

pir = MotionSensor(21)

def turn_monitor_on():
    subprocess.run("DISPLAY=:0.0 xrandr --output HDMI-1 --auto --rotate left", shell=True)
    print("Monitor turned on.")

def turn_monitor_off():
    subprocess.run("DISPLAY=:0.0 xrandr --output HDMI-1 --off", shell=True)
    print("Monitor turned off.")

def schedule_monitor_off():
    schedule.clear()
    schedule.every(5).minutes.do(turn_monitor_off)
    print("Monitor off scheduled in 5 minutes.")

while True:
    pir.wait_for_motion()
    turn_monitor_on()
    schedule_monitor_off()
    # Check periodically for new motion and run scheduled jobs.
    # If new motion is detected, break out to restart the cycle.
    while not pir.motion_detected:
        schedule.run_pending()
        time.sleep(1)

Thank you very much, that works perfectly apart from running a second time after I ctrl z to stop the script running.

(Mar-24-2025, 04:23 PM)snippsat Wrote: [ -> ]

(Mar-24-2025, 08:49 AM)lif Wrote: [ -> ]if movement is detected and off with the command 'DISPLAY=:0.0 xrandr --output HDMI-1 --off' after, say, 5 minutes.

As mention use subprocess and is better to use eg schedule when you need to wait 5-min.

import schedule
import time
import subprocess
from gpiozero import MotionSensor

pir = MotionSensor(21)

def turn_monitor_on():
    subprocess.run("DISPLAY=:0.0 xrandr --output HDMI-1 --auto --rotate left", shell=True)
    print("Monitor turned on.")

def turn_monitor_off():
    subprocess.run("DISPLAY=:0.0 xrandr --output HDMI-1 --off", shell=True)
    print("Monitor turned off.")

def schedule_monitor_off():
    schedule.clear()
    schedule.every(5).minutes.do(turn_monitor_off)
    print("Monitor off scheduled in 5 minutes.")

while True:
    pir.wait_for_motion()
    turn_monitor_on()
    schedule_monitor_off()
    # Check periodically for new motion and run scheduled jobs.
    # If new motion is detected, break out to restart the cycle.
    while not pir.motion_detected:
        schedule.run_pending()
        time.sleep(1)

lif

woooee

lif

snippsat

lif