I would like to be able to type in a specific IP address into the serial monitor and have that number be used as the NTP website IP address to get the time from. I took the NTP example that came pre-loaded with the arduino library, and combined it with Robins example in post #1
#include <SPI.h>
#include <Ethernet.h>
#include <EthernetUdp.h>
// Enter a MAC address for your controller below.
// Newer Ethernet shields have a MAC address printed on a sticker on the shield
byte mac[] = {
0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
unsigned int localPort = 8888; // local port to listen for UDP packets
IPAddress timeServer(132, 163, 4, 101); // time-a.timefreq.bldrdoc.gov NTP server
// IPAddress timeServer(132, 163, 4, 102); // time-b.timefreq.bldrdoc.gov NTP server
// IPAddress timeServer(132, 163, 4, 103); // time-c.timefreq.bldrdoc.gov NTP server
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
EthernetUDP Udp;
//-----------------------------From Robins Example----------------------
const byte numChars = 32;
char receivedChars[numChars];
boolean newData = false;
//-----------------------------------------------------------------------
void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
// start Ethernet and UDP
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to configure Ethernet using DHCP");
// no point in carrying on, so do nothing forevermore:
for(;;)
;
}
Udp.begin(localPort);
}
void loop() {
recvWithStartEndMarkers();
showNewData();
}
void recvWithStartEndMarkers() {
static boolean recvInProgress = false;
static byte ndx = 0;
char startMarker = '<';
char endMarker = '>';
char rc;
// if (Serial.available() > 0) {
while (Serial.available() > 0 && newData == false) {
rc = Serial.read();
if (recvInProgress == true) {
if (rc != endMarker) {
receivedChars[ndx] = rc;
ndx++;
if (ndx >= numChars) {
ndx = numChars - 1;
}
}
else {
receivedChars[ndx] = '\0'; // terminate the string
recvInProgress = false;
ndx = 0;
newData = true;
}
}
else if (rc == startMarker) {
recvInProgress = true;
}
}
}
void showNewData() {
if (newData == true) {
//sendNTPpacket(timeServer); // send an NTP packet to a time server
sendNTPpacket(receivedChars);
// wait to see if a reply is available
delay(1000);
if ( Udp.parsePacket() ) {
// 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(':');
if ( ((epoch % 3600) / 60) < 10 ) {
// In the first 10 minutes of each hour, we'll want a leading '0'
Serial.print('0');
}
Serial.print((epoch % 3600) / 60); // print the minute (3600 equals secs per minute)
Serial.print(':');
if ( (epoch % 60) < 10 ) {
// In the first 10 seconds of each minute, we'll want a leading '0'
Serial.print('0');
}
Serial.println(epoch %60); // print the second
}
}
}
// send an NTP request to the time server at the given address
unsigned long sendNTPpacket(IPAddress& address)
{
// 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();
}
The error message is
UdpNtpClient.ino: In function 'void showNewData()':
UdpNtpClient:89: error: invalid initialization of non-const reference of type 'IPAddress&' from a temporary of type 'char*'
UdpNtpClient:13: error: in passing argument 1 of 'long unsigned int sendNTPpacket(IPAddress&)'
The problem is here, I just don't know what I need to fix it to make it work. Can it be done?
//sendNTPpacket(timeServer); // send an NTP packet to a time server
sendNTPpacket(receivedChars);