NTP Time Server + MQTT + Node-red

/*
  Udp NTP Client
  Get the time from a Network Time Protocol (NTP) time server
  Demonstrates use of UDP sendPacket and ReceivePacket
  For more on NTP time servers and the messages needed to communicate with them,
  see http://en.wikipedia.org/wiki/Network_Time_Protocol
  created 4 Sep 2010    by Michael Margolis
  modified 9 Apr 2012  by Tom Igoe
  updated for the ESP8266 12 Apr 2015   by Ivan Grokhotkov
  This code is in the public domain.
*/

#include <ESP8266WiFi.h>
#include <WiFiUdp.h>
#include <PubSubClient.h>

// Change the variable to your Raspberry Pi IP address, so it connects to your MQTT broker
const char* mqtt_server = "iot.eclipse.org";
//const char* mqtt_server = "broker.mqtt-dashboard.com";


// Initializes the espClient. You should change the espClient name if you have multiple ESPs running in your home automation system
WiFiClient espClient;
PubSubClient client(espClient);

char ssid[] = "My ASUS1";  //  your network SSID (name)
char pass[] = "alex9981";       // your network password


unsigned int localPort = 2390;      // local port to listen for UDP packets

/* Don't hardwire the IP address or we won't get the benefits of the pool.
    Lookup the IP address for the host name instead */
//IPAddress timeServer(129, 6, 15, 28); // time.nist.gov NTP server
IPAddress timeServerIP; // time.nist.gov NTP server address
const char* ntpServerName = "clock.stdtime.gov.tw";

const int NTP_PACKET_SIZE = 48; // NTP time stamp is in the first 48 bytes of the message

byte packetBuffer[ NTP_PACKET_SIZE]; //buffer to hold incoming and outgoing packets

// A UDP instance to let us send and receive packets over UDP
WiFiUDP udp;

const int strobe = 4;   //D2
const int clock = 5;    //D1
const int data = 16;    //D0


String getNTP() {
  String msg="";
  //get a random server from the pool
  WiFi.hostByName(ntpServerName, timeServerIP);
  sendNTPpacket(timeServerIP); // send an NTP packet to a time server
  // wait to see if a reply is available
  delay(1000);
  int cb = udp.parsePacket();
  if (!cb) {
    Serial.println("no packet yet");
  }
  else
  {
    Serial.print("packet received, length=");
    Serial.println(cb);
    // We've received a packet, read the data from it
    udp.read(packetBuffer, NTP_PACKET_SIZE); // read the packet into the buffer

    //the timestamp starts at byte 40 of the received packet and is four bytes,
    // or two words, long. First, esxtract the two words:

    unsigned long highWord = word(packetBuffer[40], packetBuffer[41]);
    unsigned long lowWord = word(packetBuffer[42], packetBuffer[43]);
    // combine the four bytes (two words) into a long integer
    // this is NTP time (seconds since Jan 1 1900):
    unsigned long secsSince1900 = highWord << 16 | lowWord;
    Serial.print("Seconds since Jan 1 1900 = ");
    Serial.println(secsSince1900);

    // now convert NTP time into everyday time:
    Serial.print("Unix time = ");
    // Unix time starts on Jan 1 1970. In seconds, that's 2208988800:
    const unsigned long seventyYears = 2208988800UL;
    // subtract seventy years:
    unsigned long epoch = secsSince1900 - seventyYears;
    // print Unix time:
    Serial.println(epoch);


    // print the hour, minute and second:
    Serial.print("The UTC time is ");       // UTC is the time at Greenwich Meridian (GMT)
    Serial.print((epoch  % 86400L) / 3600); // print the hour (86400 equals secs per day)
    Serial.print(':');
    int timenumber1= (((epoch  % 86400L) / 3600)+8) % 24 ;
    Dis2digit(timenumber1,0xc0);
    msg= msg+"The UTC time is "+ ((epoch  % 86400L) / 3600)+":";

    if (((epoch % 3600) / 60) < 10) {
      // In the first 10 minutes of each hour, we'll want a leading '0'
      Serial.print('0');
      msg= msg+ "0";
    }
    Serial.print((epoch  % 3600) / 60); // print the minute (3600 equals secs per minute)
   
    int timenumber2= (epoch  % 3600) / 60;
    Dis2digit(timenumber2,0xc6); 
   
    Serial.print(':');
    msg= msg+ ((epoch  % 3600) / 60)+ ":";
    if ((epoch % 60) < 10) {
      // In the first 10 seconds of each minute, we'll want a leading '0'
      Serial.print('0');
      msg= msg+ "0";
     }
    Serial.println(epoch % 60); // print the second
    int timenumber3= (epoch  %  60);
    Dis2digit_1(timenumber3,0xcc);
    msg= msg + (epoch  %  60) ;
    Serial.print("The Time meaasge send to MQTT is ");
    Serial.println(msg);
    return (msg);
    } // wait ten seconds before asking for the time again
   
}
void setup() {
  Serial.begin(115200);
  Serial.println();
  Serial.println();

  // We start by connecting to a WiFi network
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, pass);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");

  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());

  Serial.println("Starting UDP");
  udp.begin(localPort);
  Serial.print("Local port: ");
  Serial.println(udp.localPort());

  pinMode(strobe, OUTPUT);
  pinMode(clock, OUTPUT);
  pinMode(data, OUTPUT);

  sendCommand(0x8f);  // activate
  reset();

  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
 
}

// Generally, you should use "unsigned long" for variables that hold time
// The value will quickly become too large for an int to store
unsigned long previousMillis = 0;        // will store last time LED was updated

// constants won't change:
const long interval = 10000;           // interval at which to blink (milliseconds)

// Timers auxiliar variables
long now = millis();
long lastMeasure = 0;

void loop() {
  unsigned long currentMillis = millis();
 if (currentMillis - previousMillis >= interval) {
    // save the last time you blinked the LED
      previousMillis = currentMillis;
      String message;
      message=getNTP();
  //*************************************************
     if (!client.connected()) {
        reconnect();
       }
     if(!client.loop())
       client.connect("ESP8266Client");

    char msg[58];
    message.toCharArray(msg,58);

    // Publishes Temperature and Humidity values
    client.publish("alex9ufo/NTP", msg);
    Serial.print("alex9ufo/NTP: ");
    Serial.println(msg);
    message="";

  }  // (currentMillis - previousMillis >= interval)

}

// send an NTP request to the time server at the given address
void sendNTPpacket(IPAddress& address) {
  Serial.println("sending NTP packet...");
  // set all bytes in the buffer to 0
  memset(packetBuffer, 0, NTP_PACKET_SIZE);
  // Initialize values needed to form NTP request
  // (see URL above for details on the packets)
  packetBuffer[0] = 0b11100011;   // LI, Version, Mode
  packetBuffer[1] = 0;     // Stratum, or type of clock
  packetBuffer[2] = 6;     // Polling Interval
  packetBuffer[3] = 0xEC;  // Peer Clock Precision
  // 8 bytes of zero for Root Delay & Root Dispersion
  packetBuffer[12]  = 49;
  packetBuffer[13]  = 0x4E;
  packetBuffer[14]  = 49;
  packetBuffer[15]  = 52;

  // all NTP fields have been given values, now
  // you can send a packet requesting a timestamp:
  udp.beginPacket(address, 123); //NTP requests are to port 123
  udp.write(packetBuffer, NTP_PACKET_SIZE);
  udp.endPacket();
}

void sendCommand(uint8_t value)
{
  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, value);
  digitalWrite(strobe, HIGH);
}

void reset()
{
  sendCommand(0x40); // set auto increment mode
  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, 0xc0);   // set starting address to 0
  for(uint8_t i = 0; i < 16; i++)
  {
    shiftOut(data, clock, LSBFIRST, 0x00);
  }
  digitalWrite(strobe, HIGH);
}

void Dis2digit(int num1,int addr1)
{
                       /*0*/ /*1*/ /*2*/ /*3*/ /*4*/ /*5*/ /*6*/ /*7*/ /*8*/ /*9*/
  uint8_t digits[] = { 0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d, 0x7d, 0x07, 0x7f, 0x6f ,0x00};

  int number1=num1;
  int n1=number1/10;
  int n0=number1%10;

 //0xc0  第8個 七段   0xc2  第7個 七段   0xc4   第6個 七段   0xc6  第5個 七段  0xc8  第4個 七段
 //0xc1   第8個 LED   0xc3  第7個 LED   0xc5   第6個 LED   0xc7   第5個 LED  0xc9   第4個 LED 
  sendCommand(0x44);  // set single address
  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, addr1); // 4st digit 7-segment display
  shiftOut(data, clock, LSBFIRST, digits[n1]);
  digitalWrite(strobe, HIGH);

  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, addr1+2); // 3st digit 7-segment display
  shiftOut(data, clock, LSBFIRST, digits[n0]);
  digitalWrite(strobe, HIGH);

  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, addr1+4); // 3st digit 7-segment display
  shiftOut(data, clock, LSBFIRST, 0x40);
  digitalWrite(strobe, HIGH);

}

void Dis2digit_1(int num1,int addr1)
{
                       /*0*/ /*1*/ /*2*/ /*3*/ /*4*/ /*5*/ /*6*/ /*7*/ /*8*/ /*9*/
  uint8_t digits[] = { 0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d, 0x7d, 0x07, 0x7f, 0x6f ,0x00};

  int number1=num1;
  int n1=number1/10;
  int n0=number1%10;

 //0xc0  第8個 七段   0xc2  第7個 七段   0xc4   第6個 七段   0xc6  第5個 七段  0xc8  第4個 七段
 //0xc1   第8個 LED   0xc3  第7個 LED   0xc5   第6個 LED   0xc7   第5個 LED  0xc9   第4個 LED 
  sendCommand(0x44);  // set single address
  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, addr1); // 4st digit 7-segment display
  shiftOut(data, clock, LSBFIRST, digits[n1]);
  digitalWrite(strobe, HIGH);

  digitalWrite(strobe, LOW);
  shiftOut(data, clock, LSBFIRST, addr1+2); // 3st digit 7-segment display
  shiftOut(data, clock, LSBFIRST, digits[n0]);
  digitalWrite(strobe, HIGH);

}


// This functions is executed when some device publishes a message to a topic that your ESP8266 is subscribed to
// Change the function below to add logic to your program, so when a device publishes a message to a topic that
// your ESP8266 is subscribed you can actually do something
void callback(String topic, byte* message, unsigned int length) {
}

// This functions reconnects your ESP8266 to your MQTT broker
// Change the function below if you want to subscribe to more topics with your ESP8266
void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    /*
     YOU MIGHT NEED TO CHANGE THIS LINE, IF YOU'RE HAVING PROBLEMS WITH MQTT MULTIPLE CONNECTIONS
     To change the ESP device ID, you will have to give a new name to the ESP8266.
     Here's how it looks:
       if (client.connect("ESP8266Client")) {
     You can do it like this:
       if (client.connect("ESP1_Office")) {
     Then, for the other ESP:
       if (client.connect("ESP2_Garage")) {
      That should solve your MQTT multiple connections problem
    */
    if (client.connect("ESP8266Client")) {
      Serial.println("connected"); 
      // Subscribe or resubscribe to a topic
      // You can subscribe to more topics (to control more LEDs in this example)
      client.subscribe("alex9ufo/NTP");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}