{HowTo} turn on/off your monitor (Time based, PIR/Button, App)

randomnoise

@hnperkins if the script is working the opposite way round it could be that you have a pir board which uses inverted signals. The board I had originally worked this way. So when no motion is detected it gives you a 1 & when you move it gives you a 0. Instead of running the script try typing gpio read 0 (substitute the pin number you used here… remember gpio “wiring pi” numbering will be different to the number you input in your file. See https://pinout.xyz/). It only shows the current state so you need to keep putting this in as you move in front of the sensor to test it. Hit up + enter to “retype” the command quickly in the console.

If this is the case then unfortunately the script will not work in your case… it’s written for true or 1 to be when movement is detected.

If you use paviro’s module there is a configuration option to invert the input pin.

As to the screen being black when starting mm. It’s probably an error in your configuration. Search the forum to find info on how to check the config as that has been well covered.

hnperkins

@randomnoise ok so when i do the gpio read command it always shows a 1, when i use a pin its not connected to it shows a 0, is this what you were talking about?

randomnoise

@hnperkins yes, if it’s always showing a 1 then your sensor is ‘inverted’ to the standard way most pir boards work. Note it should go to 0 when the pir detects movement (you might need to continually wave your hand in front of the pir at the exact moment you hit enter after typing the gpio read to see the 0. If you never see a 0 then you may have a faulty pir).

Although I initially did get my ‘inverted’ sensor working using the invert configuration option in paviros module, it eventually stopped working correctly (my mirror would register a false detection every 3 mins or so causing my screen to stay always on). Not sure why it broke… seemed to happen after I upgraded to a newer version of mm, but issue didn’t go away after I tried rolling back. Final thing I did to stop false triggering was to install a ferrite choke on my input wire & to move where my pi sat at the back of my monitor (it was quite close to the monitors power converter initially).

Ultimately the way I got it working was to buy a different pir board (the kind with the 2 potentiometers for sensitivity & time adjustment) which also happened to be 0 for no movement & 1 for movement). I then used the pir.py script instead of the module to trigger screen on / off. I was fairly sure it wasn’t a single faulty pir unit (mine came in a pack of 3) but nothing I did got it working so in the end spending an extra fiver on a different type of pir seemed worth it to me.

fabbr

I had the script running and all I got was “…” turns out I had the POWER and GROUND swapped because I was following the drawing on the initial post. I suggest looking at the your PIR board to make sure you are connecting the wires on the correct order.

Overall fantastic write up. Thanks for sharing

hnperkins

@fabbr i just got it working today. hadn’t had time to mess with it much. i was able to invert it in the config for the plugin and its been working great

fabbr

I used the method 2.2 Using PIR-Script and it work fine however, after a long period of time (that the screen is off and I am not doing anything on the raspberry) when I move in front of the PIR I can see the ON signal is sent to my monitor (the monitor LED change) but all I get is a blank screen.

I did some testing and notice that when I connect with VNC to the raspberry the screen immediately comes back on so it makes me wonder if there’s some kind of screensaver or something of that nature that is on.

Does anyone knows anything about this or had this problem before?

Mykle1

@fabbr

Have you disabled the screensaver? The easiest, most common way of doing that is to install xscreensaver and disable the screensaver that way

fabbr

@Mykle1 Thank you that was the problem. Xscreensaver was easy use. Thanks

Another problem I had was: when I changed the orientation of my monitor when it was coming back on all I saw was a black screen… so I did more research and found that that I could replace the tvservice for:

vcgencmd display_power 0 turns off the screen

vcgencmd display_power 1 turns on the screen

That worked better with my monitor for some reason.

blebbens

Thanks for this tutorial…

I am using a PIR. The monitor switches on immediately after detection of motion. I am looking for an option to switch on the monitor if a person stands in front of it for 10 seconds. Mine is a floor mirror, so some people are crossing the floor many times a day without looking at the mirror.

cruunnerr

@blebbens said in {HowTo} turn on/off your monitor (Time based, PIR/Button, App):

Thanks for this tutorial…

I am using a PIR. The monitor switches on immediately after detection of motion. I am looking for an option to switch on the monitor if a person stands in front of it for 10 seconds. Mine is a floor mirror, so some people are crossing the floor many times a day without looking at the mirror.

If u use the external PIR script (point 2.2) u could try to change line 25 in the script and define a TURNON-DELAY.

if turned_off and time.time() >= TURNON_DELAY:

The whole script would look like this:

#!/usr/bin/env python

import sys
import time
import RPi.GPIO as io
import subprocess

io.setmode(io.BCM)
SHUTOFF_DELAY = 120 # in seconds, how long the monitor will be on until next button press or PIR detection
TURNON_DELAY = 10
PIR_PIN = 22       # 15 on the board (this needn't to be a PIR. Can be a button also)
LED_PIN = 16      # optional, don't use as Relay-PIN. It just shows detection time of the PIR without delay time

def main():
    io.setup(PIR_PIN, io.IN)
    io.setup(LED_PIN, io.OUT)
    turned_off = False
    last_motion_time = time.time()

    while True:
        if io.input(PIR_PIN):
            last_motion_time = time.time()
            io.output(LED_PIN, io.LOW)
            print ".",
            sys.stdout.flush()
            if turned_off and time.time() >= TURNON_DELAY:
                turned_off = False
                turn_on()
        else:
            if not turned_off and time.time() > (last_motion_time + 
                                                 SHUTOFF_DELAY):
                turned_off = True
                turn_off()
            if not turned_off and time.time() > (last_motion_time + 1):
                io.output(LED_PIN, io.HIGH)
        time.sleep(.1)

def turn_on():
	subprocess.call("sh /home/pi/monitor_on.sh", shell=True)

def turn_off():
	subprocess.call("sh /home/pi/monitor_off.sh", shell=True)

if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        io.cleanup()

Don’t know if it will work. Just brainstorming cause i haven’t much time