Hi, I want to try to use a raspberry pi or an arduino to unlock the door at my place. The video intercom at my place is Fermax 7" smile monitor. I was hoping that it was going to be a simple push button activating a relay which would unlock the door, but turns out that it has got a micro controller and so much more.

Basically how the unit works is when someone buzzes to my flat the unit turns on and then I could unlock the door. I am not able to unlock the door or turn on the video unless some one buzzes.

The button is very peculiar too. I couldn't figure out how it connects the VCC or GND to the micro controller pin. The mechanism is that there is a spring on top of the button and when pressed it presses on the pcb . There is some sort of a mesh just below the button in the middle layer of the pcb. There was a via (which seems to come from the button) near the unlock button which I traced up to a pin of the micro. I tried pressing the button but it didn't show any voltage difference at the pin - maybe the unit doesn't turn on or I'm not pressing it correctly.



Here is the picture of the wall mount which the unit connects to. The white wire is the data buss according to the manual.

Any idea on how I could go further?
I'm interested in these kind of hardware hacks so please do let me know any good resources.
Thanks so much in advance.

 

Hi, I want to try to use a raspberry pi or an arduino to unlock the door at my place.

Why? I mean, what do expect the Arduino to do? Do you want it to take total control over the lock regardless of what the current device does? The current device requires a human to press a button, do you want to eliminate that?

What's on the lock end? I'm wondering if the lock receives a digital signal or just a simple signal (a voltage) over that white wire. Life would be simple if it's the latter. If you knew what the digital signal looked like, you could probably replicate it with your Arduino.

 

The idea is to eventually have the raspberry pi or arduino connected over the wifi - so that I could unlock the door when some one buzzes with out having to go near the unit. Normally I'm at the next floor.

The easier way I think would be to have a small wire running out of the unit which connects the unlock button pin and one of the arduino pin. But still I couldn't figuire out where to tap into and which voltage it operates on.

 

The easiest way is to just buy a new lock.

https://www.amazon.com/August-Smart...687&sr=8-1&keywords=home+automation+door+lock

That way it works when you want it to work.

 

The easiest way is to just buy a new lock.

https://www.amazon.com/August-Smart...687&sr=8-1&keywords=home+automation+door+lock

That way it works when you want it to work.

This is hardly a solution. OP is Looking for an intercom/public /shared door lock. Not a front door lock.

 

Hi, I want to try to use a raspberry pi or an arduino to unlock the door at my place. The video intercom at my place is Fermax 7" smile monitor. I was hoping that it was going to be a simple push button activating a relay which would unlock the door, but turns out that it has got a micro controller and so much more.

Basically how the unit works is when someone buzzes to my flat the unit turns on and then I could unlock the door. I am not able to unlock the door or turn on the video unless some one buzzes.

The button is very peculiar too. I couldn't figure out how it connects the VCC or GND to the micro controller pin. The mechanism is that there is a spring on top of the button and when pressed it presses on the pcb . There is some sort of a mesh just below the button in the middle layer of the pcb. There was a via (which seems to come from the button) near the unlock button which I traced up to a pin of the micro. I tried pressing the button but it didn't show any voltage difference at the pin - maybe the unit doesn't turn on or I'm not pressing it correctly.

View attachment 164171 View attachment 164172 View attachment 164173

Here is the picture of the wall mount which the unit connects to. The white wire is the data buss according to the manual.
View attachment 164174
Any idea on how I could go further?
I'm interested in these kind of hardware hacks so please do let me know any good resources.
Thanks so much in advance.

Did you make and headway in this?
from my testing/research the smile doesn’t just simply take a voltage to open the door. I think it does at the lock side, but not on the intercom controller. The intercom gets all its “data” over the but line, so the open door command/sequence will be sent to a localised controller which then sends the high or low voltage to the door mechanism. It’s a bit difficult to test/change hardware on the shared door side, but possible to do so on the intercom unit.

Alos it looks like I can open the door by waking the intercom and the pressing the door lock (ie. No need to have some one but first)