Strip Down Guide for BenQ 28" VA Monitor GC2870H

  • @yep_dd You could use relay with a small delay to power your backlight. So the screen will only be visible after the “HDMI1” box disappeared. Personally I wouldn’t bother with it, though.

  • @yep_dd I have not yet try, i will do my test as soon as i receive my mirror, but 3 secs look not too long

  • @madscientist okay, so after a couple of days I am absolutely satisfied. I turn on my monitor with a small httpserver python script whenever someone is at home and -if it is night- any HUE light is on. I am now thinking of changing this to different energy saving modes in my magicmirror:

    • Always On
    • On when someone is home
    • On when someone is home and any light is on (turns off at night)
    • Only on when activated by PIR / Radar Sensor

    0_1540763201051_Screenshot 2018-10-28 at 22.46.15.png

  • Hi,

    I have removed the boot logo, but it’s around 5 seconds to start the display and the “hdmi” message is there. I will try to cut the wire in the next days.

  • @yep_dd
    Nice project, I got the same glass but a different monitor.
    At my mirror the backlite seems to bright so it’s easy to locate the edge of the monitor.
    Could you take some pictures for me to be sure it’s my monitor and not a general problem with the type of glas?
    If it’s different to yours I might have to invest in a different monitor. 😅

  • @daniel3490 hi Daniel, it is bit hard to take down the mirror by myself, i have to wait until I have a friend over to help me. I don’t really see the edges of my monitor unless it is really really dark.

  • Hi @yep_DD

    Fantastic Work !

    May I ask how did you connect your rcwl0516 sensor and what module did you use to integrate it with MM? Are there any instructions I can follow?


  • @bachoo786 The sensor should have three pins: VCC, GND and signal out. You connect them the same way you connect a PIR sensor and it should also work with the same MM module MMM-PIR-Sensor.

  • Hi @bachoo786

    thank you so much. As @MadScientist pointed out the three pins are connected directly to the Raspberry. For evaluating the state I use a small http server (see below). The important parts are where the you can find anything with


    If you want I can reduce the code to what is important for you. This is the complete server which allows control of

    • ARD Livestream
    • ARD Tagesschau
    • Lowering / Increasing volume
    • Radar Sensor (just the last couple lines of code (search for: GPIO.add_event_detect)
    • Powerin On / Off Monitor by http Request (used if no one is at home / and at night)

    For me the radar sensor is just a backup. I use the power control mainly like this:

    • If someone is at home and it is between sunrise / sunset, turn on the monitor(1)
    • If someone is at home but it is night and all lights are off, turn off the monitor(1)
    • If someone is in front of the monitor turn it on by radar

    (1) is done via FHEM (a home automation running on another raspberry, it calls my mirror like this: (monitor on) (monitor off) or /down (for volume) and so on.

    #!/usr/bin/python3 -u
    host_name = ''  # Change this to your Raspberry Pi IP address
    host_port = 8000
    proc = ''
    monitorstatus = 'unknown'
    import RPi.GPIO as GPIO
    from pathlib import Path
    import os
    import subprocess
    import signal
    from subprocess import call
    from time import sleep
    from http.server import BaseHTTPRequestHandler, HTTPServer
    SENSOR_PIN = 24
    class MyServer(BaseHTTPRequestHandler):
        def monitor_on(channel): #define initial status of Monitor
            if monitorstatus!="on":
                status='Monitor on by Radar Sensor'
                subprocess.Popen(["/usr/bin/vcgencmd", "display_power", "1"], preexec_fn=os.setsid)
        def do_HEAD(self):
            self.send_header('Content-type', 'text/html')
        def do_GET(self):
            global proc
            global monitorstatus
            html = '''
               <h1>Magic Mirror Control</h1>
               <p>Current GPU temperature is {}</p>
               <p>Podcast: <a href="/play">Play</a> <a href="/stop">Stop</a></p>
               <p>ARD Livestream: <a href="/ard">Play</a> <a href="/stop">Stop</a></p>
               <p>Volume: <a href="/down">down</a> <a href="/up">up</a></p>
               <p>System: <a href="/shutdown">Shutdown</a> <a href="/restart">Restart</a></p>
               <p>Monitor: <a href="/on">On</a> <a href="/off">Off</a></p>
            temp = os.popen("/opt/vc/bin/vcgencmd measure_temp").read()
            status = ''
            if self.path=='/':
                #GPIO.setup(17, GPIO.IN)
            elif self.path=='/play':
                if proc=='':
                    my_file = Path("/home/pi/MagicMirror/video.mp4")
                    if my_file.is_file():
                        statinfo = os.stat('/home/pi/MagicMirror/video.mp4')
                        if statinfo.st_size > 0:
                            proc = subprocess.Popen(["omxplayer", "-o", "alsa:hw:ALSA", "--no-osd", "/home/pi/MagicMirror/video.mp4"], preexec_fn=os.setsid)
                            status='Playing Podcast'
                            proc = subprocess.Popen(["omxplayer", "-o", "alsa:hw:ALSA", "--no-osd", "/home/pi/MagicMirror/Loading.mp4"], preexec_fn=os.setsid)
                            status='Not yet available'
                        proc = subprocess.Popen(["omxplayer", "-o", "alsa:hw:ALSA", "--no-osd", "/home/pi/MagicMirror/Loading.mp4"], preexec_fn=os.setsid)
                        status='Not yet available'
                    status='Stopping Podcast'
                    os.killpg(os.getpgid(, signal.SIGTERM)
            elif self.path=='/ard':
                if proc=='':
                    proc = subprocess.Popen(["livestreamer", "hlsvariant://", "best", "-vnp", "omxplayer -o alsa:hw:ALSA --no-osd --timeout 20"], preexec_fn=os.setsid)
                    status='Playing ARD Livestream'
                    status='Stopping Stream'
                    os.killpg(os.getpgid(, signal.SIGTERM)
            elif self.path=='/stop':
                if proc!='':
                    status='Stopping Podcast'
                    os.killpg(os.getpgid(, signal.SIGTERM)
                    status='Nothing to stop'
            elif self.path=='/shutdown':
                subprocess.Popen(["sudo", "shutdown", "-h", "now"], preexec_fn=os.setsid)
            elif self.path=='/restart':
                subprocess.Popen(["sudo", "reboot"], preexec_fn=os.setsid)
            elif self.path=='/down':
                status='Volume down'
                subprocess.Popen(["amixer", "set", "Master", "8%-"], preexec_fn=os.setsid)
            elif self.path=='/up':
                status='Volume up'
                subprocess.Popen(["amixer", "set", "Master", "8%+"], preexec_fn=os.setsid)
            elif self.path=='/on':
                if monitorstatus!="on": #switch on Monitor if status was off (by httpRequest NOT Radar)
                    status='Monitor on'
                    subprocess.Popen(["/usr/bin/vcgencmd", "display_power", "1"], preexec_fn=os.setsid)
            elif self.path=='/off':
                if monitorstatus!="off": #switch off Monitor if status was on  (by httpRequest NOT Radar)
                    status='Monitor off'
                    subprocess.Popen(["/usr/bin/vcgencmd", "display_power", "0"], preexec_fn=os.setsid)
            self.wfile.write(html.format(temp[5:], status).encode("utf-8"))
    if __name__ == '__main__':
        http_server = HTTPServer((host_name, host_port), MyServer)
        print("Server Starts - %s:%s" % (host_name, host_port))
            GPIO.add_event_detect(SENSOR_PIN , GPIO.RISING, callback=MyServer.monitor_on) #detect radar sensor and enable Monitor
        except KeyboardInterrupt:

  • @MadScientist @yep_DD Thanks for the replies. Is there anyway to limit the distance that the radar sensor senses? I have my magic mirror in the bath room and it faces the wooden door which I believe will be detecting motion through it and I don’t want that.