Módulo transceptor LoRa SX1262

Módulo transceptor LoRa SX1262

El módulo LoRa Core1262-868M incorpora un chip RF SX1262 de nueva generación, mayor eficiencia energética y mayor distancia de transmisión que el SX1278 tradicional, con una alta capacidad anti interferencia.

Programas realizados con STEAMakers Blocks

Con esta disposición de pines, de forma que DIO1 esté conectado al GPIO12 del ESP32, RESET al GPIO13, CS al GPIO5, CLK al GPIO18, MOSI al GPIO23 y MISO al GPIO19 y el entorno de programación de STEAMakers Blocks no he conseguido que funcione. 

 

También he probado que DIO1 esté conectado al GPIO14 del ESP32, RESET al GPIO12, CS al GPIO5, CLK al GPIO18, BUSY al GPIO 13, MOSI al GPIO23 y MISO al GPIO19, pero tampoco he conseguido que funcione en el entorno de programación de STEAMakers Blocks.

Programas de thekakester

En Github podemos encontrar unos sencillos programas para este transceptor. Están probados con una placa Adafruit Metro ESP32-S2 Express.

Ejemplo de recepción

#include "LoraSx1262.h"

LoraSx1262* radio;
byte receiveBuff[255];

void setup() {
  Serial.begin(9600);
  Serial.println("Booted");

  radio = new LoraSx1262();
}

void loop() {
  //Receive a packet over radio
  int bytesRead = radio->lora_receive_async(receiveBuff, sizeof(receiveBuff));

  if (bytesRead > -1) {
    //Print the payload out over serial
    Serial.print("Received: ");
    Serial.write(receiveBuff,bytesRead);
    Serial.println(); //Add a newline after printing
  }
}

Ejemplo de transmisión

#include "LoraSx1262.h"

byte payload = "Hello world.  This a pretty long payload. We can transmit up to 255 bytes at once, which is pretty neat if you ask me";
LoraSx1262* radio;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  Serial.println("Booted");

  radio = new LoraSx1262();
}

void loop() {
  Serial.print("Transmitting... ");
  radio->transmit(payload,strlen(payload));
  Serial.println("Done!");

  delay(1000);
}

Uso de la librería RadioLib

RadioLib permite a sus usuarios integrar todo tipo de módulos de comunicación inalámbrica, protocolos e incluso modos digitales en un único sistema consistente. Se pueden encontrar variados programas para Arduino y SX1262. (Wiki)

SX126x Channel Activity Detection Receive

 /*

  RadioLib SX126x Receive after Channel Activity Detection Example

  This example uses SX1262 to scan the current LoRa

  channel and detect ongoing LoRa transmissions.

  Unlike SX127x CAD, SX126x can detect any part

  of LoRa transmission, not just the preamble.

  If a packet is detected, the module will switch

  to receive mode and receive the packet.

  Other modules from SX126x family can also be used.

  For default module settings, see the wiki page

  https://github.com/jgromes/RadioLib/wiki/Default-configuration#sx126x---lora-modem

  For full API reference, see the GitHub Pages

  https://jgromes.github.io/RadioLib/

*/

// include the library

#include <RadioLib.h>

// SX1262 has the following connections:

// NSS pin:   10

// DIO1 pin:  2

// NRST pin:  3

// BUSY pin:  9

SX1262 radio = new Module(10, 2, 3, 9);

// or detect the pinout automatically using RadioBoards

// https://github.com/radiolib-org/RadioBoards

/*

#define RADIO_BOARD_AUTO

#include <RadioBoards.h>

Radio radio = new RadioModule();

*/

// whether we are receiving, or scanning

bool receiving = false;

// flag to indicate that a packet was detected or CAD timed out

volatile bool scanFlag = false;

// this function is called when a complete packet

// is received by the module

// IMPORTANT: this function MUST be 'void' type

//            and MUST NOT have any arguments!

#if defined(ESP8266) || defined(ESP32)

  ICACHE_RAM_ATTR

#endif

void setFlag(void) {

  // something happened, set the flag

  scanFlag = true;

}

void setup() {

  Serial.begin(9600);

  // initialize SX1262 with default settings

  Serial.print(F("[SX1262] Initializing ... "));

  int state = radio.begin();

  if (state == RADIOLIB_ERR_NONE) {

    Serial.println(F("success!"));

  } else {

    Serial.print(F("failed, code "));

    Serial.println(state);

    while (true) { delay(10); }

  }

  // set the function that will be called

  // when LoRa packet or timeout is detected

  radio.setDio1Action(setFlag);

  // start scanning the channel

  Serial.print(F("[SX1262] Starting scan for LoRa preamble ... "));

  state = radio.startChannelScan();

  if (state == RADIOLIB_ERR_NONE) {

    Serial.println(F("success!"));

  } else {

    Serial.print(F("failed, code "));

    Serial.println(state);

  }

}

void loop() {

  // check if the flag is set

  if(scanFlag) {

    int state = RADIOLIB_ERR_NONE;

    // reset flag

    scanFlag = false;

    // check ongoing reception

    if(receiving) {

      // DIO triggered while reception is ongoing

      // that means we got a packet

      // you can read received data as an Arduino String

      String str;

      state = radio.readData(str);

 

      // you can also read received data as byte array

      /*

        byte byteArr[8];

        state = radio.readData(byteArr, 8);

      */

   

      if (state == RADIOLIB_ERR_NONE) {

        // packet was successfully received

        Serial.println(F("[SX1262] Received packet!"));

 

        // print data of the packet

        Serial.print(F("[SX1262] Data:\t\t"));

        Serial.println(str);

 

        // print RSSI (Received Signal Strength Indicator)

        Serial.print(F("[SX1262] RSSI:\t\t"));

        Serial.print(radio.getRSSI());

        Serial.println(F(" dBm"));

 

        // print SNR (Signal-to-Noise Ratio)

        Serial.print(F("[SX1262] SNR:\t\t"));

        Serial.print(radio.getSNR());

        Serial.println(F(" dB"));

 

        // print frequency error

        Serial.print(F("[SX1262] Frequency error:\t"));

        Serial.print(radio.getFrequencyError());

        Serial.println(F(" Hz"));

 

      } else {

        // some other error occurred

        Serial.print(F("[SX1262] Failed, code "));

        Serial.println(state);

 

      }

      // reception is done now

      receiving = false;

     

    } else {

      // check CAD result

      state = radio.getChannelScanResult();

      if (state == RADIOLIB_LORA_DETECTED) {

        // LoRa packet was detected

        Serial.print(F("[SX1262] Packet detected, starting reception ... "));

        state = radio.startReceive();

        if (state == RADIOLIB_ERR_NONE) {

          Serial.println(F("success!"));

        } else {

          Serial.print(F("failed, code "));

          Serial.println(state);

        }

        // set the flag for ongoing reception

        receiving = true;

      } else if (state == RADIOLIB_CHANNEL_FREE) {

        // channel is free

        Serial.println(F("[SX1262] Channel is free!"));

      } else {

        // some other error occurred

        Serial.print(F("[SX1262] Failed, code "));

        Serial.println(state);

      }

    }

    // if we're not receiving, start scanning again

    if(!receiving) {

      Serial.print(F("[SX1262] Starting scan for LoRa preamble ... "));

      state = radio.startChannelScan();

      if (state == RADIOLIB_ERR_NONE) {

        Serial.println(F("success!"));

      } else {

        Serial.print(F("failed, code "));

        Serial.println(state);

      }

   

    }

  }

   

}

Uso de la librería Ra01S

En Github nopnop2002 tiene ejemplos de código para programar SX1262 en Arduino.

Conexiones entre SX1262 y ESP32

CONEXIONES SX1262 ↔ ESP32

Función SX1262 Pin del SX1262 Conectar al pin ESP32 Descripción

NSS / CS         CS / NSS     GPIO 5 (recomendado) Chip Select SPI

SCK         SCK     GPIO 18                         SPI Clock

MOSI         MOSI     GPIO 23                         SPI Master Out

MISO         MISO     GPIO 19                         SPI Master In

DIO1         DIO1     GPIO 14                         Interrupciones / eventos

BUSY         BUSY     GPIO 13                         Señal de ocupado

NRST         RESET     GPIO 12                         Reset del SX1262

3.3V         VCC     3V3 ESP32                         Alimentación

GND         GND     GND                                 Tierra común