How to simulate an intercom button press? (need to hack door intercom to open entry door into my building for delivery)

RobDYI · March 31, 2018, 1:18am

You are correct with the understanding of my pictures in that you have to cut the solder where the red line and connect a wire where the blue line is.

Th good news is that the low voltage sonoff that you found I think would work as is. It appears to have a normal relay so you can connect your intercom wires normally open (self locking mode 1).

I think you can use a simple voltage divider on the 12V power to cut the voltage to the low volt sonoff of 5v. You need to buy two resister to get the correct voltage division as per below.

https://learn.sparkfun.com/tutorials/voltage-dividers

myle · March 31, 2018, 3:10am

Thought of that but I don’t feel happy cutting a sonoff

5v can ONLY take 5v well I wouldn’t
Put anything more that 5v

namadori · March 31, 2018, 6:42am

There is a less known sonoff that can be powered 7-32v ac/dc and has a relay output.

amirandap · March 31, 2018, 10:10pm

I have this working with my intercom and a raspberry PI, right now it detects when someone rings my apartment, plays a mp3 file directly into the speaker line, records whatever comes from the door microphone and then automatically opens the door.

Initially i wanted to get a notificiation with the recorded file so i could then decide to open, but my ADD kicked in and i left it to automatically open door 4 seconds after somebody rings my door.

Let me know if you want the code

Coolie1101 · April 1, 2018, 1:12am

@B1tMaster
If you use Z-Wave, a MIMOlite would be the simplest way.

B1tMaster · April 1, 2018, 1:05pm

@amirandap, that would be awesome! Please point me to your source code and instructions.

B1tMaster · April 1, 2018, 1:15pm

@Coolie1101, Thank you. I do use Z-Wave. Let me look into MIMOlite and see what it is.

B1tMaster · April 3, 2018, 11:32pm

@amirandap, I think your solution is most advanced and would also allow me to capture and alert me of somebody ringing my door downstairs. How do I contact you and get access to your code?

Thank you very much.

amirandap · April 4, 2018, 12:47am

What brand is your intercom? I never got around to getting the HTTP API into the code, which would allow it to work with HA, it currently opens door automatically, but it should be fairly easy to code.

Heres the code, its not optimal but works

http://collabedit.com/jn86r

#!/usr/bin/python3
import RPi.GPIO as GPIO
import subprocess
import shlex
from time import sleep

def greeting():
    command_line = 'aplay /home/pi/Desktop/greeting.wav'
    args = shlex.split(command_line)
    subprocess.call(args)

def answer():
    command_line = 'sudo arecord -D plughw:1 --duration=3 -f cd /home/pi/Desktop/answer.wav'
    args = shlex.split(command_line)
    subprocess.call(args)
   
def pulsador():
        if (GPIO.input(16)):
            GPIO.output(11, 1)
            GPIO.output(7, 1)
            sleep(2)
            greeting()
            answer()
            GPIO.output(11, 0)
            GPIO.output(7, 0)
            GPIO.output(13, 1)
            sleep(2)
            GPIO.output(13, 0)
        
        
if __name__ == '__main__':
    try: 
        GPIO.setmode(GPIO.BOARD)
        GPIO.setup(16, GPIO.IN)
        GPIO.setwarnings(False)
        GPIO.setup(7, GPIO.OUT, initial=0)   
        GPIO.setup(11, GPIO.OUT, initial=0)
        GPIO.setup(13, GPIO.OUT, initial=0)
        while True:
            pulsador()
        
    except KeyboardInterrupt:
        GPIO.cleanup()
        exit(0)
    except Exception as e:
        print("Error:")
        print(e)            
    finally:
        GPIO.cleanup()
        exit(1)

B1tMaster · April 4, 2018, 2:39pm

@amirandap,
Thank you very much. Do you mind explaining how this works? This runs on a separate PI attached to your intercom? Do you have schematics on which pins on your RPi are attached where on intercom?

My intercom brand is Fermax (model is Citymax ).
From the manual below, it seem that I need to trip together wire 1 and 3 on my intercom once somebody rings the bell to open the door.

https://github.com/B1tMaster/haas-config/files/1862571/94727_EN.Esquemario.4N.Citymax.V_05_03.pdf
(manual )

My issue: https://github.com/B1tMaster/haas-config/issues/89

But I am not sure how I would play sound back… or how can I detect that somebody is ringing… (which pins would carry current to indicate that. )

If you could share more details on how your code works maybe I can figure out how to make it work on my intercom.

I attached two pictures of intercom and how it connects

amirandap · April 4, 2018, 3:22pm

I will try to take it apart and take pictures again but since its a different model you will have to get a voltage tester and start taking measurements to see which one aplies the 12v to the line when you press the line.

Yes it runs on a separate raspberry zero that is inside the gang box. In order to keep the original intercom working i bought another intercom and took out the main pcb, so they work in parallel.

For the audio i just soldered the wires from the intercom headset to a usb external sound card

juancarlos · December 5, 2018, 12:11am

I’d like to grab the code too, if you please.
Also, where on the intercom do you connect the device? Is a wire connected to each side of the BUZZ button, closing the circuit when the device is activated?

sogeniusio · January 26, 2020, 12:54am

Was this code ever shared? I’m currently trying to accomplish the same here.

Edit: I think I found it here: https://github.com/amirandap/Smart-Intercom

pergola.fabio · January 26, 2020, 7:39am

I am also still interested in this stuff, I have an entrya intercom system.
. Already captured the button press and video, so I have an notification in HA with video when someone rings the doorbell…
But my audio is missing, I want to capture audio / microphone too… So I can’t actually speak

So tips are welcome how to solder and stuff like that

augustose · September 8, 2020, 6:13pm

I did the basic door open button with a shelly 1PM

See the info here

SINCE1992 · February 27, 2021, 3:20pm

Hi there,

Could you share some more info with me. It looks like I have the same setup for my front door. I saw your pictures but couldnt find out how you connected your Shelly 1PM to which cables etc…

@augustose

augustose · March 29, 2021, 9:58pm

Hello @SINCE1992 from both sides of the door opening button I connected the Shelly:O and Shelly:L1.

Then the Shelly:L and Shely:N to the electricity 110v.

Does that answer the question ?

Laskomex · August 19, 2021, 4:19pm

Hi, I have intercom Laskomex LN-8.
Possible to make open the front door via sonoff switch without ringing from to street ?

Hellis81 · August 19, 2021, 4:48pm

Open your door and press the button that opens the door outside.
Do you hear a sound in the staircase?
Or if it’s too far have someone go down an listen/try open the door.

Laskomex · August 19, 2021, 6:45pm

No. I possible to open the door from inside only if ringing my house outside.