sender.ino

/*
 * HART Industrial Unions, LLC
 * Erik J. Reynolds
 * 2019-11-13
 * 
 * Position Sensor Switch Status Sender
 */

// includes
#include <SPI.h>
#include <RH_RF69.h>
#include <RHReliableDatagram.h>

// radio setup
#define RF69_FREQ 915.0

// Metro M4 Airlift
#define RFM69_CS      11
#define RFM69_INT     0
#define RFM69_RST     1
#define LED           13

// Where to send packets to!
#define DEST_ADDRESS   1
// change addresses for each client board, any number :)
// 2 == Air Compressor
// 3+ == future
#define MY_ADDRESS     2

// Singleton instance of the radio driver
RH_RF69 rf69(RFM69_CS, RFM69_INT);

// Class to manage message delivery and receipt, using the driver declared above
RHReliableDatagram rf69_manager(rf69, MY_ADDRESS);

const int sensor = 4;

int state; // 0 = closed/contact, 1 = open/no-contact

void setup() {
  //Serial.begin(115200); // serial console only used if connected to a computer for testing anyways

  pinMode(sensor, INPUT_PULLUP); // reed relay
  pinMode(LED, OUTPUT);     
  pinMode(RFM69_RST, OUTPUT);
  digitalWrite(RFM69_RST, LOW);

  // manual reset
  digitalWrite(RFM69_RST, HIGH);
  delay(10);
  digitalWrite(RFM69_RST, LOW);
  delay(10);
  
  if (!rf69_manager.init()) {
    //Serial.println(F("RFM69 radio init failed"));
    while (1);
  }
  //Serial.println(F("RFM69 radio init OK!"));
  // Defaults after init are 434.0MHz, modulation GFSK_Rb250Fd250, +13dbM (for low power module)
  // No encryption
  if (!rf69.setFrequency(RF69_FREQ)) {
    //Serial.println(F("setFrequency failed"));
  }

  // If you are using a high power RF69 eg RFM69HW, you *must* set a Tx power with the
  // ishighpowermodule flag set like this:
  rf69.setTxPower(20, true);  // range from 14-20 for power, 2nd arg must be true for 69HCW

  // The encryption key has to be the same as the one in the server
  // this is the default key from the example code but sure why not
  uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
                    0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08};
  rf69.setEncryptionKey(key);
  
  pinMode(LED, OUTPUT);

  //Serial.print("RFM69 radio @");  
  //Serial.print((int)RF69_FREQ);  
  //Serial.println(" MHz");
}

uint8_t buf[RH_RF69_MAX_MESSAGE_LEN]; // receive buffer
uint8_t data[] = "  OK"; // I don't know what this is used for.

void loop() {
  
  state = digitalRead(sensor);
  char radiopacket[20] = "AIRCOMPRESSOR: ";
  
  if (state == HIGH) {
    // NO CONTACT
    strcat(radiopacket, "OFF");
  } else {
    // CONTACT
    strcat(radiopacket, "ON");
  }
  
  //Serial.print(F("Sending "));
  //Serial.println(radiopacket);
  
  // Send a message to the DESTINATION!
  if (rf69_manager.sendtoWait((uint8_t *)radiopacket, strlen(radiopacket), DEST_ADDRESS)) {
    // Now wait for a reply from the server
    uint8_t len = sizeof(buf);
    uint8_t from;   
    if (rf69_manager.recvfromAckTimeout(buf, &len, 2000, &from)) {
      buf[len] = 0; // zero out remaining string
      
      //Serial.print(F("Got reply from #")); Serial.print(from);
      //Serial.print(F(" [RSSI :"));
      //Serial.print(rf69.lastRssi());
      //Serial.print(F("] : "));
      //Serial.println((char*)buf);     
      Blink(LED, 40, 3); //blink LED 3 times, 40ms between blinks
    } else {
      //Serial.println(F("No reply, is anyone listening?"));
    }
  } else {
    //Serial.println(F("Sending failed (no ack)"));
  }
  
  // Wait a second...
  delay(1000);
}

void Blink(byte PIN, byte DELAY_MS, byte loops) {
  for (byte i=0; i<loops; i++)  {
    digitalWrite(PIN,HIGH);
    delay(DELAY_MS);
    digitalWrite(PIN,LOW);
    delay(DELAY_MS);
  }
}