nodemcu与xl1276-D01 Lora(433MHz SPI)的完美邂逅

简介

Lora是一种远距离传输的协议，在这个项目中，我们尝试与XL1276-D01 LoRa（433MHz）进行点对点连接，我们使用NodeMCU作为主控板。

提示：使用xl1278也可以。

在这个项目中，将包含发送器和接收器两个部分。

步骤一 材料清单

硬件：

• Nodemcu开发板*2
• XL1276-D01 LoRa模块*2或xl1278
• 若干杜邦线
• 面包板

软件：

• Arduino IDE

步骤二 硬件搭建

• ANT =>天线焊接
• GND => GND
• DIO1 => D2 / GPIO 4
• VCC => 3.3V
• DIO0 => D1 / GPIO 5
• RESET => D0 / GPIO 16
• SCK => D5 / GPIO 14
• MISO => D6 / GPIO 12
• MOSI => D7 / GPIO 13
• NSS => D8 / GPIO 15

发送器和接收器部分的连接与上面的引脚定义中所示的相同。

步骤四 开始编程

对于传输和接收，我们需要两个Arduino IDE同时运行。因此，我们需要打开两个Arduino IDE，最好是在不同的盘里面的软件，这样的目的是用两个不同的串口监视器。同时运行两个并将代码复制到Arduino IDE。

在编译代码之前，需要先下载LORA1276的库文件，下载地址：

发送器和接收器的完整代码如下：

发送器代码：

#include "SX1278.h"
#include 

#define LORA_MODE  4
#define LORA_CHANNEL  CH_6_BW_125
#define LORA_ADDRESS  2

#define LORA_SEND_TO_ADDRESS  4

#define LORA_LED  9

int e;

char message1 [] = "Packet 1, wanting to see if received packet is the same as sent packet";
char message2 [] = "Packet 2, broadcast test";

void setup()
{
  pinMode(LORA_LED, OUTPUT);

  // Open serial communications and wait for port to open:
  Serial.begin(9600);

  // Print a start message
  Serial.println(F("sx1278 module and Arduino: send two packets (One to an addrees and another one in broadcast)"));

  // Power ON the moduleif (sx1278.ON() == 0) {
    Serial.println(F("Setting power ON: SUCCESS "));
  } else {
    Serial.println(F("Setting power ON: ERROR "));
  }

  // Set transmission mode and print the result if (sx1278.setMode(LORA_MODE) == 0) {
    Serial.println(F("Setting Mode: SUCCESS "));
  } else {
    Serial.println(F("Setting Mode: ERROR "));
  }

  // Set headerif (sx1278.setHeaderON() == 0) {
    Serial.println(F("Setting Header ON: SUCCESS "));
  } else {
    Serial.println(F("Setting Header ON: ERROR "));
  }

  // Select frequency channelif (sx1278.setChannel(LORA_CHANNEL) == 0) {
    Serial.println(F("Setting Channel: SUCCESS "));
  } else {
    Serial.println(F("Setting Channel: ERROR "));
  }

  // Set CRCif (sx1278.setCRC_ON() == 0) {
    Serial.println(F("Setting CRC ON: SUCCESS "));
  } else {
    Serial.println(F("Setting CRC ON: ERROR "));
  }

  // Select output power (Max, High, Intermediate or Low)if (sx1278.setPower('M') == 0) {
    Serial.println(F("Setting Power: SUCCESS "));
  } else {
    Serial.println(F("Setting Power: ERROR "));
  }

  // Set the node address and print the resultif (sx1278.setNodeAddress(LORA_ADDRESS) == 0) {
    Serial.println(F("Setting node address: SUCCESS "));
  } else {
    Serial.println(F("Setting node address: ERROR "));
  }

  // Print a success message
  Serial.println(F("sx1278 configured finished"));
  Serial.println();
}

void loop(void)
{
  // Send message1 and print the result
  e = sx1278.sendPacketTimeout(LORA_SEND_TO_ADDRESS, message1);
  Serial.print(F("Packet sent, state "));
  Serial.println(e, DEC);

  if (e == 0) {
      digitalWrite(LORA_LED, HIGH);
      delay(500);
      digitalWrite(LORA_LED, LOW);
  }

  delay(4000);  

  // Send message2 broadcast and print the result
  e = sx1278.sendPacketTimeout(0, message2);
  Serial.print(F("Packet sent, state "));
  Serial.println(e, DEC);

  if (e == 0) {
      digitalWrite(LORA_LED, HIGH);
      delay(500);
      digitalWrite(LORA_LED, LOW);
  }

  delay(4000);  
}

接收器代码：

当你编译时，请记住在“工具”选项卡中将开发板设置更改为NodeMCU，如图所示。完成上传后，打开每侧的串行监视器。您将首先看到配置设置。完成所有配置后，发送器将开始发送消息，您可以在接收器看到收到的消息。

步骤五 最终演示