RAK11720 Breakout Board with ESP32

LPWAN Modules / EVBs RAK11720
1

I want to know whether it’s possible to connect the Breakout Board with ESP32?

2

Welcome to the forum @razarahil

You can connect the ESP32 with one of it’s UARTS to UART0_TX and UART0_RX of the RAK11720.
Then you can control the RAK11720 with AT commands from the ESP32.

3

I tried the basic AT command, but no responsewas received. I’ve connected the 3v3 and gnd on the right-hand side where the UART0 pins are located.

My code:

#include <Arduino.h>

// Define UART pins for the RAK module (adjust according to your wiring)
#define RAK_RX_PIN  16  // Pin on ESP32C6 used for receiving data (connected to RAK TX)
#define RAK_TX_PIN  17  // Pin on ESP32C6 used for transmitting data (connected to RAK RX)

void setup() {
  // Start the Serial Monitor for debugging
  Serial.begin(115200);
  while (!Serial);  // Wait for the Serial Monitor to be available
  
  // Initialize a second hardware serial port for the RAK module
  // Using Serial1 with specified RX and TX pins
  Serial1.begin(115200, SERIAL_8N1, RAK_RX_PIN, RAK_TX_PIN);
  delay(2000);  // Allow some time for the module to initialize
  
  Serial.println("Sending AT command to RAK module...");
  Serial1.println("AT");  // Send the basic AT command
}

void loop() {
  // Check if data is available from the RAK module
  if (Serial1.available()) {
    String response = Serial1.readStringUntil('\n');
    Serial.print("Module Response: ");
    Serial.println(response);
  }
  
  // Optionally, you could resend the AT command periodically if needed:
  // delay(5000);
  // Serial1.println("AT");
}
4

Did you cross RX and TX lines?

RX RAK11720 <==> TX ESP32
TX RAK11720 <==> RX ESP32

Did you try connecting a computer to the RAK11720 with a terminal app and check that it responds to AT commands?

5

Yes, I’ve crossed check but still not responding.
I tried with Putty command and it’s responded to AT command.

6

Then you have to check your serial setup in the ESP32

115200 Baud, 8 bit, no parity, 1 stop bit

AT commands must be ending with CR/LF