ESP-Temperature-DeepSleep.ino

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

extern "C" {
#include "user_interface.h"
}


//
// Wifi
//
const char *ssid     = "***********";
const char *password = "***********";
WiFiClient client;


void setup() {
  Serial.begin(115200);

  //
  //  Wifi
  //
  WiFi.begin ( ssid, password );
  Serial.println("Started");
  
  // Wait for connection
  while ( WiFi.status() != WL_CONNECTED ) {
    delay ( 500 );
    Serial.print ( "." );
  }
  Serial.println("Wifi Connected");

  sendTemperature();
  
  ESP.deepSleep(55*1000*1000, WAKE_RF_DISABLED);
  delay(1000);
}


void loop() {
}



void sendTemperature() {
  char buffer[20];
  float t = readTemperature();
  dtostrf(t, 2,1, buffer);
  Serial.println(buffer);

  String postStr = "&field1=" + String(buffer);
  send(postStr);

  Serial.println(postStr);
}

void send(String inPostStr) {
  String apiKey = "**********************";         
  Serial.print("Connecting...");
  if (client.connect("184.106.153.149", 80)) {  //  api.thingspeak.com
    Serial.print("Connected....");
    String postStr = apiKey + inPostStr + "\r\n\r\n";
    client.print("POST /update HTTP/1.1\n");
    client.print("Host: api.thingspeak.com\n");
    client.print("Connection: close\n");
    client.print("X-THINGSPEAKAPIKEY: " + apiKey + "\n");
    client.print("Content-Type: application/x-www-form-urlencoded\n");
    client.print("Content-Length: ");
    client.print(postStr.length());
    client.print("\n\n");
    client.print(postStr);
    Serial.println("posted.");
  }
  client.stop();
}



float readTemperature() {
  float v = system_adc_read() / 1.062000 * 2.00000;  // mV

  return 30.00000 - (v - 1474.000) / 8.2000000;
}