B4R Question Necessary hardware to doorbell

I would use a ESP32 connecting either by Wi-Fi (built-in) or GSM using a SIM900 module.
ESP32 is powerfull enough to perform any of he tasks you mentioned and easily integratable and upgradable.

I use an ESP8266 Lolin + Telegram for that.

EDIT: I read now about taking a picture sorry.

Edit2: I know a company using something like this:taking the picture and sending it to the cloud example here: https://www.roboremo.com/jpeg-camera--esp8266.html

Thank you both!

I will start to search some Esp board, breadboard, ...

f0raster0 said:

I know a company using something like this

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Not sure if I could make it work with B4X

José J. Aguilar said:

Not sure if I could make it work with B4X

Click to expand...

It's only a matter of having the lib for that camera, but there are other cameras, and I recall seeing a lib for one in the b4r forum

Just don't buy the esp32 with camera piggyback... Seems that eve Arduino IDE has s hard time with those

Pi zero W plus a Pi camera. You can control the camera with B4J shell commands. Might want to look at MotionEyeOS for the pi.

Again, thank you guys!
Probably I start just with the esp32 to play with it, I will see more pobilities later

From what you said I guess what you need to use is:
1. An old smartphone with gsm SIM card
2. Arduino Uno
3. Bluetooth module (HC05 or similar)
4. A few glue components (resistors..etc)

* Door bell (push button) and BT are connected to Uno.
** Uno sends button state to door smartphone
*** well, you know the rest of the story.

My 2 cents

Beja said:

From what you said I guess what you need to use is:
1. An old smartphone with gsm SIM card
2. Arduino Uno
3. Bluetooth module (HC05 or similar)
4. A few glue components (resistors..etc)

* Door bell (push button) and BT are connected to Uno.
** Uno sends button state to door smartphone
*** well, you know the rest of the story.

My 2 cents

Click to expand...

That solution implies 2 espérante power suplies, one for the phone and another for the électronics.
All needed electronics can easily be powered by a single PSU and without the need of b4r + b4a coding, only b4r.

Cableguy said:

Just don't buy the esp32 with camera piggyback... Seems that eve Arduino IDE has s hard time with those

Click to expand...

Are you referring to the ESP32-CAM module?
When this was first released it was only supported by the native Espressif IDF, it is however now supported by the Arduino IDE and a very comprehensive example sketch can be found HERE.

Cableguy said:

That solution implies 2 espérante power suplies, one for the phone and another for the électronics.
All needed electronics can easily be powered by a single PSU and without the need of b4r + b4a coding, only b4r.

Click to expand...

You are right Cableguy, still depends on the complexity and requirements. May be some initial facial recognitions and conversation with visitors ... Etc are required . then b4a is more flexible and powerful, in terms of memory and processing.

I have a wifi camera at the main gate, sending live images to a androin tablet. At the bell pushbutton there is a ESP32 which publishes a message to Firebase to connected smartphones. I can see the same movie on the smartphones everywhere they are. And see who is ringing.

Beja said:

You are right Cableguy, still depends on the complexity and requirements. May be some initial facial recognitions and conversation with visitors ... Etc are required . then b4a is more flexible and powerful, in terms of memory and processing.

Click to expand...

Indeed, but as always, there's more than just one way to skin a cat!

José J. Aguilar said:

What I'd like to do in my job:
1.- Someone rings the doorbell.
2.- Something (arduino? raspberry?, ESPxxxx?) gets the signal and I send to some mobile phones a notify (MQTT or Firebase)
3.- Click in the notification, my app opens, and then I click a button and send a signal to open the door

Click to expand...

These are the initial requirements, easily achieved under 20€, then the OP decided to add visuals by means of a camera (taking just still frames) and we are still under 35€...
Then, the OP moves onto video, which is a completely different ball game hardware requirements wise, and we jump up to over 50€ solution... There are already commercial solutions at that price range...

This is my camera (I've 5 of them in my property)https://www.ebay.it/itm/IP-CAMERA-P2P-TELECAMERA-WIRELESS-WIFI-IR-INFRAROSSI-IPCAM-SD-PER-ESTERNO-604/382617803654?hash=item5915cc5b86:g:fVsAAOSwFZZb3dOl
they are ONVIF cameras, so they can be seen on the web with no problem.
The expense is to bring electric power to each. I sacrificed the functionality and kept them all around my house, exept the one at the main gate. This limits the need for new wires.

An ESP32-CAM board can do the lot for just £5.82!
Admittedly it's video streaming performance is mediocre, sometimes working fine sometimes stalls and lags.
I've added a PIR sensor to my ESP32-CAM, this wakes the ESP32-CAM when motion is detected.
The ESP32-CAM wakes, takes a picture then connects to my network and uploads the picture (via a webSocket).
While the ESP32-CAM is awake it'll send a new picture to my server every 10 seconds or so.
After 60 seconds of no motion detected the ESP32-CAM goes into deep sleep mode, awaiting the next motion detection.
All low cost stuff but works very well!

Hi again, and thanks everyone for the answers. I haven't answer before because I wanted to have something more to say

I've received an ESP8266 board:


Tested successfully the button sample, and mqtt sample.
Now I'm trying to test the FCM sample, sending the message when I press a button. I get the notify in my android from FCM console, but not from the B4J app, not from the B4R samples (get success messages in logs, but nothing in mobile). I'm making more test and I'll open a new thread when fall into despair

Beja said:

* Door bell (push button) and BT are connected to Uno.

Click to expand...

I didn't explain my real needs in the first post. I'm not trying to build a doorbell from the top, but I want to implement it in a existing 220v doorbell existing in my job's warehouse.

With the help of some workmate, I have this relay. (I've bought a cheap 220v doorbell to test)


When I get 220v in one side, I get a closed contact on the other side, so I hope it works when my test of sending the message when pressing the button works. (of course, I'm aware of the danger of 220v AC current, I'll be cautious...)

The next step will be to see what kind of signal opens the narrow door (you don't want to see the box where the cables are ...)

warwound said:

An ESP32-CAM board can do the lot for just £5.82!

Click to expand...

I would love it. Probably when this is working, I'll make more test with a cam. BTW, yesterday I saw this:
https://tech.scargill.net/espressif-esp-eye-board/

I'll keep you informed.

Be very careful! A tipical "basic" doorbell with electric latch uses a transformer to power up the needed circuitry!

Take the time to take voltage measurements on all possible points and try to sketch up a basic wiring diagram of the existing circuit.
I would be very surprised if you mesure anything over 24v at any "human interaction" points.

220V in door bell? It's quite dangerous, think of moisture... Use a power supply with a low voltage, like Cableguy wrote.