Farm-Data-Relay-System/Sensors/DS18B20_8266/DS18B20_8266.ino

//  FARM DATA RELAY SYSTEM
//
//  DS18B20 SENSOR MODULE
//
//  Developed by Timm Bogner (bogner1@gmail.com) for Sola Gratia Farm in Urbana, Illinois, USA.
//  Each sensor is assigned a two-byte identifier along with a one-byte sensor type
//

#define TERM_MAC    0x00 //Terminal MAC
#define SLEEPYTIME  30   //Time to sleep in seconds
#define TEMP_ID     4    //Unique ID (0 - 255) for each data reading
#define ONE_WIRE_BUS 13   //Pin that the DS18B20 is connected to

#include <ESP8266WiFi.h>
#include <espnow.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include "DataReading.h"

uint8_t broadcastAddress[] = {0xAA, 0xBB, 0xCC, 0xDD, 0xEE, TERM_MAC};
int wait_time = 0;
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void OnDataSent(uint8_t *mac_addr, uint8_t sendStatus) {
  Serial.print("Last Packet Send Status: ");
  if (sendStatus == 0) {
    Serial.println("Delivery success");
  }
  else {
    Serial.println("Delivery fail");
  }
}

void setup() {
  Serial.begin(115200);
  WiFi.mode(WIFI_STA);
  if (esp_now_init() != 0) {
    return;
  }

  esp_now_set_self_role(ESP_NOW_ROLE_COMBO);
  esp_now_register_send_cb(OnDataSent);
  // Register peer
  esp_now_add_peer(broadcastAddress, ESP_NOW_ROLE_COMBO, 0, NULL, 0);

  sensors.begin();

}

void loop() {
  if (millis() > wait_time) {
    wait_time = wait_time + SLEEPYTIME * 1000;
    loadData();
  }
}
void loadData() {
  sensors.requestTemperatures(); // Send the command to get temperatures
  float tempC = sensors.getTempCByIndex(0);
  DataReading Temp;
  Temp.id = TEMP_ID;
  Temp.t = 1;
  //  if (tempC = DEVICE_DISCONNECTED_C) Temp.d = -69.00;
  //  else Temp.d = tempC;
  Temp.d = tempC;
  esp_now_send(broadcastAddress, (uint8_t *) &Temp, sizeof(Temp));

}