time_ntp_esp_ardu.ino

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

char ssid[] = "************";  
char pass[] = "**************";     


unsigned int localPort = 2390;    

IPAddress timeServer(129, 6, 15, 28); 

const int NTP_PACKET_SIZE = 48; 

byte packetBuffer[ NTP_PACKET_SIZE]; 


WiFiUDP udp;

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

  WiFi.begin(ssid, pass);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }


  udp.begin(localPort);

}

void loop()
{
  sendNTPpacket(timeServer); 
  delay(1000);
  
  int cb = udp.parsePacket();
  
    udp.read(packetBuffer, NTP_PACKET_SIZE); 

    unsigned long highWord = word(packetBuffer[40], packetBuffer[41]);
    unsigned long lowWord = word(packetBuffer[42], packetBuffer[43]);

    unsigned long secsSince1900 = highWord << 16 | lowWord;

    const unsigned long seventyYears = 2208988800UL;
    unsigned long epoch = secsSince1900 - seventyYears;
    
    int stund  = (epoch  % 86400L) / 3600 + 1;
    int minut   = (epoch  % 3600) / 60;
    int sekunde = epoch % 60;
    String stunde = String(stund);
    String minutestring = String(minut);
    if(minut < 10)
    {
      minutestring = "0" + minutestring;  
    }


    Serial.println(stunde);
    Serial.println("|");
    Serial.println(minutestring);
    Serial.println("|");
    Serial.println(sekunde);
    Serial.println("|");

  delay(10000);
}


unsigned long 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();
}