NTP_Clock.ino

/*

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

#include "LedControl.h"

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

/*
 Now we need a LedControl to work with.
 ***** These pin numbers will probably not work with your hardware *****
 pin 12 is connected to the DataIn 
 pin 11 is connected to the CLK 
 pin 10 is connected to LOAD 
 We have only a single MAX72XX.
 */
LedControl lc=LedControl(13,14,15,1);

#define WS2812_PIN 4

// Parameter 1 = number of pixels in strip
// Parameter 2 = Arduino pin number (most are valid)
// Parameter 3 = pixel type flags, add together as needed:
//   NEO_KHZ800  800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)
//   NEO_KHZ400  400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
//   NEO_GRB     Pixels are wired for GRB bitstream (most NeoPixel products)
//   NEO_RGB     Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)
Adafruit_NeoPixel strip = Adafruit_NeoPixel(6, WS2812_PIN , NEO_GRB + NEO_KHZ800);


#define black_color  strip.Color(0 ,0, 0)
#define red_color    strip.Color(32 ,0, 0)
#define yellow_color strip.Color(32 ,32, 0)
#define green_color  strip.Color(0 ,32, 0)
#define cyan_color   strip.Color(0 ,32, 32)
#define blue_color   strip.Color(0 ,0, 32)
#define purple_color strip.Color(32 ,0, 32)
#define white_color  strip.Color(32 ,32, 32)

uint32_t bg_color[] = { black_color, red_color, yellow_color,
                        green_color, cyan_color, blue_color,
                        purple_color,white_color};


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 = "time.nist.gov";

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;
uint8_t Hour,Min,Sec;

unsigned long tick_disp = 0;        // will store last time LED was updated
unsigned tick_Sync = 0;

const long interval = 1000;           // interval at which to blink (milliseconds)

int num;

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.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());

  /*
   The MAX72XX is in power-saving mode on startup,
   we have to do a wakeup call
   */
  lc.shutdown(0,false);
  /* Set the brightness to a medium values */
  lc.setIntensity(0,8);
  /* and clear the display */
  lc.clearDisplay(0);

  strip.begin();
  strip.show(); // Initialize all pixels to 'off'

  syncTime();
}

void loop()
{  

  unsigned long currentMillis = millis();

  if (currentMillis - tick_disp >= interval) {
    tick_disp = currentMillis;

    lc.setDigit(0,0,(Hour/10)%10   ,false);
    lc.setDigit(0,1,(Hour%10),false);
    lc.setDigit(0,2,(Min/10)%10    ,false);
    lc.setDigit(0,3,(Min%10),false);
    lc.setDigit(0,4,(Sec/10)%10    ,false);
    lc.setDigit(0,5,(Sec%10)       ,false);

    Sec++;
    if(Sec>59) {
      Sec = 0;
      Min++;
      num++;
    }
    if (Min>59) {
      Min = 0;
      Hour++;
    }
    if (Hour>23) {
      Hour =0;
    }

    colorWipe(bg_color[num], 0);    
    if (num > 8) num =0;    

  }

  if (currentMillis - tick_Sync >= 10000) {
    Serial.println("Sync time packet...");
    tick_Sync = currentMillis;    
    syncTime();        
  }
  
}

void syncTime() {
    //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)
    Hour = ( (epoch  % 86400L) / 3600 ) + 7 ;
    Min = (epoch  % 3600) / 60;
    Sec =  epoch % 60;

    if (Hour>23) {
      Hour =0;
    }

    
    Serial.print(Hour); // print the hour (86400 equals secs per day)
    Serial.print(':');
    Serial.print(Min); // print the minute (3600 equals secs per minute)
    Serial.print(':');
    Serial.println(Sec); // print the second
  }
  // wait ten seconds before asking for the time again
  //delay(10000);
}
// send an NTP request to the time server at the given address
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();
}

// Fill the dots one after the other with a color
void colorWipe(uint32_t c, uint8_t wait) {
  for(uint16_t i=0; i<strip.numPixels(); i++) {
    strip.setPixelColor(i, c);
    strip.show();
    delay(wait);
  }
}