RCSwitch library seemingly not working for 433 Hz receiver on ESP32 NodeMCU

I'm pretty new to Arduino and especially ESP32. But - before I receive the tip "use an Arduino" - I decided to go for the ESP32 because of the size and the capability to connect it to the WLAN.

However, I am trying to build some control box for my terrarium which should - in the first design - steer various lamps and the rain pump via remote controlled outlets. For this I got an ESP32 NodeMCU, a RTC time module (which seems to work quite fine) and a 433 Hz receiver/sender set.

I followed several tutorials regarding the wiring and uploaded the example files to the ESP32. No matter which pin I connect the Receiver to (I need to connect the receiver first in order to read out the signals of the 433 Hz control which came with the outlets) I won't receive any signals on the receiver.

I embedded the library RCSwitch and I tried to configure my switch as follows (here with PIN 13 as example - I tried several other pins as well):

mySwitch.enableReceive(13)

As I read in some other blog, there might be the need to convert the pin number to its interrupt address, so I tried the following:

mySwitch.enableReceive(digitalPinToInterrupt(13))

The result is always the same: dead silence on the serial monitor (except the boot messages, etc.).

Am I using the wrong library or what am I doing wrong here?

I read that there should be a library called RFSwitch, but the only version I found only features the 433 Hz sender, not the receiver.

I would be really grateful for any hint concerning this issue - I'm pretty stuck here for many hours now...

Solution

Have been successful with RCSwitch today on ESP32 Dev Board and a 433MHZ receiver and sender. Here is what I have been stumbling on my journey.

Connecting the receiver (requires 5V)

You can use the ESP32-VIN for 5V if the Micro-USB is used to supply power
You may connect the Receiver-DATA to any ESP-32-Input-PIN BUT you might damage your ESP32 since it only allows ~3.3V
- I tried first with some "makeshift" level shifting through resistors but I guess it lowers speed too much => A proper level-shifter (5V => 3.3V) might work out well
- When referencing the PIN "xx" I have been just using the PIN-Number "Dxx" written on the ESP32-Dev-Board
You may connect an antenna of ~17.3cm to improve range

#include <RCSwitch.h>
RCSwitch mySwitch = RCSwitch();

#define RXD2 27

void setup() {
  Serial.begin(115200);
  Serial.print("Ready to receive.");  
  mySwitch.enableReceive(RXD2); 
}

void loop() {    
  if (mySwitch.available()) {  
    Serial.print("Received ");
    Serial.print( mySwitch.getReceivedValue() );
    Serial.print(" / ");
    Serial.print( mySwitch.getReceivedBitlength() );
    Serial.print("bit ");
    Serial.print("Protocol: ");
    Serial.print( mySwitch.getReceivedProtocol() );
    Serial.print(" / ");
    Serial.println( mySwitch.getReceivedDelay() );

    mySwitch.resetAvailable();
  }
}

In your RC and Outlet can be configured by DIP-Switches you might not need to connect the receiver overall - you can directly insert the DIP-Switches levels in the RCSwitch-Library

Connecting the sender (is fine with just 3.3V)

You can use the ESP32-3.3 to supply power
You may want to double check the PIN-Labels - I got confused because the DATA-Label was off and first interpreted as GND | DATA | VCC instead of GND | VCC | DATA
You may connect an antenna of ~17.3cm to improve range

#include <Arduino.h>
#include <WiFi.h>
#include <RCSwitch.h>

#define TXD2 25

RCSwitch mySwitch = RCSwitch();

void setup() {
  Serial.begin(115200);
  
  // Transmitter is connected to Arduino Pin #10  
  mySwitch.enableTransmit(TXD2);
  
  // Optional set protocol (default is 1, will work for most outlets)
  // mySwitch.setProtocol(2);

  // Optional set pulse length.
  mySwitch.setPulseLength(311);
  
  // Optional set number of transmission repetitions.
  // mySwitch.setRepeatTransmit(15);  
}

void loop() {
  /* See Example: TypeA_WithDIPSwitches */
  mySwitch.switchOn("01010", "10000");
  Serial.println("Switch On");
  delay(10000);
  mySwitch.switchOff("01010", "10000");
  Serial.println("Switch Off");
  delay(10000);
}

I have not yet used sender or receiver while WiFi being active. Though I have been reading about issues while WiFi is active and receiving / sending via 433Mhz.