LoRa Server rf95.available（）方法返回false

Question

我正在尝试用LoRa（rf95）将一个Arduino发送给另一个Arduino。我跟着https://www.smart-prototyping.com/blog/Sending-and-Receiving-Weather-Data-with-a-LoRa-Module enter link description here我确定引脚连接。然后我在radiohead库中使用了示例rf95服务器代码。问题是rf95.available（）方法每次都返回false。我不知道连接有什么问题。

代码：

// rf95_server.pde
// -*- mode: C++ -*-
// Example sketch showing how to create a simple messageing server
// with the RH_RF95 class. RH_RF95 class does not provide for addressing or
// reliability, so you should only use RH_RF95  if you do not need the higher
// level messaging abilities.
// It is designed to work with the other example rf95_client
// Tested with Anarduino MiniWirelessLoRa, Rocket Scream Mini Ultra Pro with
// the RFM95W, Adafruit Feather M0 with RFM95

#include <SPI.h>
#include <RH_RF95.h>

// Singleton instance of the radio driver
RH_RF95 rf95;
//RH_RF95 rf95(5, 2); // Rocket Scream Mini Ultra Pro with the RFM95W
//RH_RF95 rf95(8, 3); // Adafruit Feather M0 with RFM95 

// Need this on Arduino Zero with SerialUSB port (eg RocketScream Mini Ultra Pro)
//#define Serial SerialUSB

int led = 9;

void setup() 
{
  // Rocket Scream Mini Ultra Pro with the RFM95W only:
  // Ensure serial flash is not interfering with radio communication on SPI bus
//  pinMode(4, OUTPUT);
//  digitalWrite(4, HIGH);

  pinMode(led, OUTPUT);     
  Serial.begin(38400);
  while (!Serial) ; // Wait for serial port to be available
  if (!rf95.init())
    Serial.println("init failed");  
  // Defaults after init are 434.0MHz, 13dBm, Bw = 125 kHz, Cr = 4/5, Sf = 128chips/symbol, CRC on

  // The default transmitter power is 13dBm, using PA_BOOST.
  // If you are using RFM95/96/97/98 modules which uses the PA_BOOST transmitter pin, then 
  // you can set transmitter powers from 5 to 23 dBm:
//  driver.setTxPower(23, false);
  // If you are using Modtronix inAir4 or inAir9,or any other module which uses the
  // transmitter RFO pins and not the PA_BOOST pins
  // then you can configure the power transmitter power for -1 to 14 dBm and with useRFO true. 
  // Failure to do that will result in extremely low transmit powers.
//  driver.setTxPower(14, true);
}

void loop()
{
  Serial.println("init ");  
  if (rf95.available())
  {
    Serial.println("Available");  
    // Should be a message for us now   
    uint8_t buf[RH_RF95_MAX_MESSAGE_LEN];
    uint8_t len = sizeof(buf);
    if (rf95.recv(buf, &len))
    {
      digitalWrite(led, HIGH);
//      RH_RF95::printBuffer("request: ", buf, len);
      Serial.print("got request: ");
      Serial.println((char*)buf);
//      Serial.print("RSSI: ");
//      Serial.println(rf95.lastRssi(), DEC);

      // Send a reply
      uint8_t data[] = "And hello back to you";
      rf95.send(data, sizeof(data));
      rf95.waitPacketSent();
      Serial.println("Sent a reply");
       digitalWrite(led, LOW);
    }
    else
    {
      Serial.println("recv failed");
    }
  }else
    Serial.println("fail");
}

Answer 1

其中一个arduinos没有通过串行连接插入USB。如果是这样，那么代码可能挂在下面的行。 while（！Serial）; //等待串口可用

Answer 2

你应该尝试将int led = 9;改为int led = 8;

9根据自己的维基保留给LoRa模块的RESET引脚：

RF95-server草图使用led=9来显示状态。请将其更改为其他LED，例如8，因为9连接到LoRa模块的RESET引脚。