1 files changed, 120 insertions, 0 deletions
diff --git a/Time/Examples/TimeNTP/TimeNTP.pde b/Time/Examples/TimeNTP/TimeNTP.pde
new file mode 100644
index 0000000..11927c6
--- /dev/null
+++ b/Time/Examples/TimeNTP/TimeNTP.pde
@@ -0,0 +1,120 @@
+/*
+ * Time_NTP.pde
+ * Example showing time sync to NTP time source
+ *
+ * This sketch uses the Ethenet library with the user contributed UdpBytewise extension
+ */
+ 
+#include <Time.h> 
+#include <Ethernet.h>
+#include <UdpBytewise.h>  // UDP library from: bjoern@cs.stanford.edu 12/30/2008 
+#if  UDP_TX_PACKET_MAX_SIZE <64 ||  UDP_RX_PACKET_MAX_SIZE < 64
+#error : UDP packet size to small - modify UdpBytewise.h to set buffers to 64 bytes
+#endif
+/*
+ *
+ * You may need to modify the UdpBytewise.h library to allow enough space in the buffers for the NTP packets.
+ * Open up UdpBytewse.h and set the following buffers to 64 bytes:
+ *    #define UDP_TX_PACKET_MAX_SIZE 64
+ *    #define UDP_RX_PACKET_MAX_SIZE 64
+ */
+
+
+byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; 
+byte ip[] = { 192, 168, 1, 44 }; // set the IP address to an unused address on your network
+
+byte SNTP_server_IP[]    = { 192, 43, 244, 18}; // time.nist.gov
+//byte SNTP_server_IP[] = { 130,149,17,21};    // ntps1-0.cs.tu-berlin.de
+//byte SNTP_server_IP[] = { 192,53,103,108};   // ptbtime1.ptb.de
+
+
+time_t prevDisplay = 0; // when the digital clock was displayed
+const  long timeZoneOffset = 0L; // set this to the offset in seconds to your local time;
+
+void setup() 
+{
+  Serial.begin(9600);
+  Ethernet.begin(mac,ip);  
+  Serial.println("waiting for sync");
+  setSyncProvider(getNtpTime);
+  while(timeStatus()== timeNotSet)   
+     ; // wait until the time is set by the sync provider
+}
+
+void loop()
+{  
+  if( now() != prevDisplay) //update the display only if the time has changed
+  {
+    prevDisplay = now();
+    digitalClockDisplay();  
+  }
+}
+
+void digitalClockDisplay(){
+  // digital clock display of the time
+  Serial.print(hour());
+  printDigits(minute());
+  printDigits(second());
+  Serial.print(" ");
+  Serial.print(day());
+  Serial.print(" ");
+  Serial.print(month());
+  Serial.print(" ");
+  Serial.print(year()); 
+  Serial.println(); 
+}
+
+void printDigits(int digits){
+  // utility function for digital clock display: prints preceding colon and leading 0
+  Serial.print(":");
+  if(digits < 10)
+    Serial.print('0');
+  Serial.print(digits);
+}
+
+/*-------- NTP code ----------*/
+
+unsigned long getNtpTime()
+{
+  sendNTPpacket(SNTP_server_IP);
+  delay(1000);
+  if ( UdpBytewise.available() ) {
+    for(int i=0; i < 40; i++)
+       UdpBytewise.read(); // ignore every field except the time
+    const unsigned long seventy_years = 2208988800UL + timeZoneOffset;        
+    return getUlong() -  seventy_years;      
+  }
+  return 0; // return 0 if unable to get the time
+}
+
+unsigned long sendNTPpacket(byte *address)
+{
+  UdpBytewise.begin(123);
+  UdpBytewise.beginPacket(address, 123);
+  UdpBytewise.write(B11100011);   // LI, Version, Mode
+  UdpBytewise.write(0);    // Stratum
+  UdpBytewise.write(6);  // Polling Interval
+  UdpBytewise.write(0xEC); // Peer Clock Precision
+  write_n(0, 8);    // Root Delay & Root Dispersion
+  UdpBytewise.write(49); 
+  UdpBytewise.write(0x4E);
+  UdpBytewise.write(49);
+  UdpBytewise.write(52);
+  write_n(0, 32); //Reference and time stamps  
+  UdpBytewise.endPacket();   
+}
+
+unsigned long getUlong()
+{
+    unsigned long ulong = (unsigned long)UdpBytewise.read() << 24;
+    ulong |= (unsigned long)UdpBytewise.read() << 16;
+    ulong |= (unsigned long)UdpBytewise.read() << 8;
+    ulong |= (unsigned long)UdpBytewise.read();
+    return ulong;
+}
+
+void write_n(int what, int how_many)
+{
+  for( int i = 0; i < how_many; i++ )
+    UdpBytewise.write(what);
+}