hygrometer.cpp

#include <Arduino.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>

#include "settings.h"

#define MQTT_MAXBUFFERSIZE 250
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"

const char* ssid = "myssid";
const char* password = "mypassword";

#define MQTT_SERVER "192.168.0.7"
#define MQTT_PORT   1883

#define CYCLE_TIME 300000

#define SLEEP 600
#define SLEEP_MODE WAKE_RF_DEFAULT

WiFiClient client;
Adafruit_MQTT_Client mqtt(&client, MQTT_SERVER, MQTT_PORT, "DHT_"+ESP.getChipId() , "");

void MQTT_connect();
int measureMoisture(void);

void setup(void){
  Serial.begin(112500);
  Serial.println("");

  WiFi.begin(ssid, password);

  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(HYGRO_VCC, OUTPUT);
  digitalWrite(HYGRO_VCC, LOW);

  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    digitalWrite(LED_BUILTIN, HIGH);
    delay(100);
    digitalWrite(LED_BUILTIN, LOW);
    delay(400);
    Serial.print(".");
  }

  Serial.println("");
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
}

void loop(void){
  MQTT_connect();

  char buf[50];
  char buf_value[50];

  int val = measureMoisture();
  Serial.printf("Moisture level: %d\r\n", val);

  //Humidity
  String("soil/" + String(ESP.getChipId()) + "/value").toCharArray(buf, 50);
  String(val).toCharArray(buf_value, 50);

  Serial.print(buf);
  Serial.print(": ");
  Serial.println(buf_value);

  mqtt.publish(buf, buf_value);

  Serial.println("Going to sleep");
  ESP.deepSleep(SLEEP*1000000, SLEEP_MODE);
}

int measureMoisture(void){
  digitalWrite(HYGRO_VCC, HIGH);

  delay(10);

  long sum;
  for (int i=0;i<10;i++){
    sum += analogRead(A0);
  }
  sum = sum/10;

  Serial.printf("Raw value0: %d\r\n", sum);

  sum = 1024 - sum;

  Serial.printf("Raw value1: %d\r\n", sum);

  digitalWrite(HYGRO_VCC, LOW);

  return constrain(map(sum, HYGRO_LOW, HYGRO_HIGH, 0, 100), 0, 100);
}

void MQTT_connect() {
  int8_t ret;

  // Stop if already connected.
  if (mqtt.connected()) {
    return;
  }

  Serial.print("Connecting to MQTT... ");

  uint8_t retries = 3;
  while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected
       Serial.println(mqtt.connectErrorString(ret));
       Serial.println("Retrying MQTT connection in 5 seconds...");
       mqtt.disconnect();
       delay(5000);  // wait 5 seconds
       retries--;
       if (retries == 0) {
         // basically die and wait for WDT to reset me
         while (1);
       }
  }
  Serial.println("MQTT Connected!");
}