Ra-02 is a wireless transmission module based on SEMTECH's SX1278 wireless transceiver. It adopts advanced LoRa spread spectrum technology, with a communication distance of 10,000 meters. It has strong ability of anti-jamming and has the function of air wake-up Consumption. Can be covering thousands of people in the district environment, particularly suitable for meter reading, smart home, burglar alarm equipment.

The LoRa series module Ra-01 is designed and developed by AI-THINKER Technology. The SX1278 RF module is mainly used for long-range spread spectrum communication. It can resist Minimize current consumption. Thanks to SEMTECH's patented LoRa ™ modulation technology, the SX1278 has a high sensitivity of -148 dBm with a power output of +20 dBm, a long transmission distance and high reliability. At the same time, compared with the traditional modulation technology, LoRa ™ modulation technology has obvious advantages in anti-blocking and selection, which solves the problem that the traditional design scheme can not consider the distance, interference and power consumption at the same time.

Features:

• LoRa ™ Spread Spectrum modulation technology
• Constant RF power output at + 20dBm-100mW voltage change
• High sensitivity: down to -148dBm
• Half-duplex SPI communication
• Programmable bit rates up to 300kbps
• Supports FSK, GFSK, MSK, GMSK, LoRa ™ and OOK modulation modes
• 127dB RSSI dynamic range
• Automatic RF signal detection, CAD mode and very high speed AFC
• Packet engine with CRC up to 256 bytes
• Small footprint dual-row stamp-hole patch package
• Shielded housing
• 433Mhz Antenna

Package List:

• SX1278 433M Wireless LoRa 02 Module x 1PCS
• 1 x 433Mhz Antenna

How to interface with an Arduino?

To interface the SX1278 LoRa Module 433MHz (Ra-02 Ai-Thinker) with an Arduino, follow these steps:

Components Required:

• Arduino board (e.g., Arduino UNO, Nano, etc.)
• SX1278 LoRa Module 433MHz (Ra-02 Ai-Thinker)
• Jumper wires
• Breadboard (optional)
• Antenna for the LoRa module

Wiring Diagram:

1. SX1278 LoRa Module Pinout:

   • VCC: Connect to Arduino 3.3V (do not use 5V as it might damage the module)
   • GND: Connect to Arduino GND
   • NSS (CS): Connect to Arduino pin 10 (SPI Chip Select)
   • SCK: Connect to Arduino pin 13 (SPI Clock)
   • MISO: Connect to Arduino pin 12 (SPI MISO)
   • MOSI: Connect to Arduino pin 11 (SPI MOSI)
   • DIO0: Connect to Arduino pin 2 (Interrupt pin for receiving, optional)
   • RST: Connect to Arduino pin 9 (Reset pin, optional but recommended)
   • 3.3V: Connect to Arduino 3.3V (Power supply)

2. Arduino Pins:

   • Pin 10 (NSS): Chip Select for SPI communication
   • Pin 13 (SCK): SPI Clock
   • Pin 12 (MISO): Master In Slave Out
   • Pin 11 (MOSI): Master Out Slave In
   • Pin 9 (RST): Reset (if used)
   • Pin 2 (DIO0): Interrupt for receiving data (optional, for advanced use)

Arduino Code:

You’ll need the LoRa library for Arduino. Here’s an example to get you started:

1. Install the LoRa Library:

   • Open the Arduino IDE.
   • Go to Sketch > Include Library > Manage Libraries.
   • Search for "LoRa" and install the LoRa by Sandeep Mistry library.

2. Example Code for Transmitter:

#include <SPI.h>
#include <LoRa.h>

// Define pins
#define SS_PIN 10
#define RST_PIN 9
#define DIO0_PIN 2

void setup() {
  // Start serial communication
  Serial.begin(9600);
  while (!Serial);

  // Initialize LoRa
  Serial.println("LoRa Initializing...");
  if (!LoRa.begin(433E6)) {
    Serial.println("Starting LoRa failed!");
    while (1);
  }
  Serial.println("LoRa Initializing OK!");
}

void loop() {
  // Send a test message
  Serial.println("Sending test message...");
  LoRa.beginPacket();
  LoRa.print("Hello World!");
  LoRa.endPacket();

  // Wait 5 seconds
  delay(5000);
}

Example Code for Receiver:

#include <SPI.h>
#include <LoRa.h>

// Define pins
#define SS_PIN 10
#define RST_PIN 9
#define DIO0_PIN 2

void setup() {
  // Start serial communication
  Serial.begin(9600);
  while (!Serial);

  // Initialize LoRa
  Serial.println("LoRa Initializing...");
  if (!LoRa.begin(433E6)) {
    Serial.println("Starting LoRa failed!");
    while (1);
  }
  Serial.println("LoRa Initializing OK!");

  // Set up LoRa reception
  LoRa.receive();
}

void loop() {
  // Check if there is any LoRa data available
  int packetSize = LoRa.parsePacket();
  if (packetSize) {
    // Read the packet
    String received = "";
    while (LoRa.available()) {
      received += (char)LoRa.read();
    }
    Serial.print("Received: ");
    Serial.println(received);
  }
}

Explanation:

• LoRa.begin(433E6): Initializes the LoRa module for 433MHz communication.
• LoRa.beginPacket(): Starts a packet for sending data.
• LoRa.print("Hello World!"): Writes data to the packet.
• LoRa.endPacket(): Ends the packet and sends it.
• LoRa.receive(): Sets the module to receive mode.
• LoRa.parsePacket(): Checks if there is any incoming data.

Important Notes:

• Power Supply: Ensure that the SX1278 module is powered by 3.3V. Applying 5V can damage the module.
• Antenna: Attach the antenna to the SX1278 module for optimal performance and range.

This setup allows you to transmit and receive data using the SX1278 LoRa module with an Arduino, enabling long-range wireless communication.