Use common 433Mhz Remotes with your Smart Home Applications (e.g. via Home Assistant) by reacting to MQTT-Messages.

Device will automatically detect Connection loss from MQTT-Server or WiFi and react by reconnecting or resetting the device until the connection can be established again. This is indicated by the onboard LED blinking slowly.

Thanks to:

• https://github.com/milaq/rpi-rf for the python code to receive and send 433Mhz codes on the Raspberry Pi
• https://github.com/AdrianCX/pico433mhz which this is a fork of (especially the pico edits)

• Set up micropython on pico (use the firmware for 'Raspberry Pi Pico W (with urequests and upip preinstalled)'). See https://www.raspberrypi.com/documentation/microcontrollers/micropython.html
• Make sure to install the umqtt.robust2 package, as this is needed for publishing MQTT-messages (easily doable in thonny IDE). See https://pypi.org/project/micropython-umqtt.robust2/
• Update src/config.py with your WiFi and MQTT Config. Also set the RX-Pin Number depending on which Pin you connected the Data Pin of your receiver. Copy all files from src to Pico, e.g. via thonny IDE.

Restarting the Pico (by plugging it in) will run the main.py script.

Run src/sniffer.py and edit the codes in src/config.py according to your needs.

IMPORTANT NOTE: Codes (as well as pulselength and protocol) can vary depending on how long the button on your remote is pressed! This behaviour occurs with some types / brands of remote controls I used. Press and hold the button on your remote and observe which code is the right one (gets repeated over and over while button is pressed). The wrong config could yield messages for buttons you did not press.

[...]
{ "code": "1000002", "pulselength": "325", "protocol": "1" }

MQTT_TOPIC="topic/you/wish/to/publish/to"

CODES = {
    "1000000": {"subtopic": "A", "msg": "ON"},
    "1000001": {"subtopic": "A", "msg": "OFF"},  
    "1000002": {"subtopic": "B", "msg": "ON"}, 
    "1000003": {"subtopic": "B", "msg": "OFF"}, 
    "1000004": {"subtopic": "C", "msg": "ON"}, 
    "1000005": {"subtopic": "C", "msg": "OFF"}, 
    "1000006": {"subtopic": "D", "msg": "ON"},
    "1000007": {"subtopic": "D", "msg": "OFF"},  
}

• Make sure to meet the regulations regarding 433mhz (https://en.wikipedia.org/wiki/LPD433)
• Try to use the "right" receiver module(s). Use RXB12 instead of XY-MK-5V (https://blog.thesen.eu/433mhz-empfaenger-fuer-arduino-co-rxb12-vs-xy-mk-5v/)
• Use a coil loaded antenna, which is often sent along with the receiver, or even better build your own! (https://www.instructables.com/433-MHz-Coil-loaded-antenna/)
• The modules are rated for 3.3V i guess, but i use them with the VBUS-Pin (passes through the voltage of the USB-Port, which should be 5V).