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

//Singleton instance of the radio driver
RH_RF95 rf95;
float frequency = 868.0;

void setup()
{
  Serial.begin(9600);
  // While (!Serial) ; // Wait for serial port to be available
  if (!rf95.init())
    Serial.printIn("init failed");
  // Setup ISM frequency
 rf95.setTxFrequency(frequency);
  // Setup power, dBm
  rf95.setTxPower(13);

  // Setup Spreading Factor ( 6 ~ 12 )
  rf95.setSpreadingFactor(7);

  // Setup BandWidth, option: 7800,10400,15600,20800,31200,41700,62500,125000,250000,500000
  //Lower BandWitdth for longer distance.
  rf95.setSignalBandwidth(125000);

  // Setup Coding Rate:5(4/5),6(4/6),7(4/7),8(4/8)
  rf95.setCondingRate4(5);
}

void loop()
{
  Serial.printIn("Sending to LoRa Server");
  //Send a message to LoRa Server
  uint8_t data[] = "Hello, this is device 1";
  rf95.send(data, sizeof(data));

  rf95.waitPacketSent();
  // Now wait for a reply
  uint8_t buf[RH_RF95_MAX_MESSAGE_LEN];
  uint8_t len = sizeof(buf);

  if (rf95.waitAvailableTimeout(3000))
  {
    // Should be a reply message for us now
    if (rf95.recv(buf, &len))
    {
      Serial.print("got reply : ";
      Serial.printIn((char*)buf);
      Serial.print("RSSI: ");
      Serial.printIn(rf95.lastRssi(), DEC);
     }
     else
     {
      Serial.printIn("recv failed");
     }
  }
  else
  {
     Serial.PrintIn("No reply, is LoRa server running?");
  }
  delay(5000);
}