ESP8266 Community Forum

- Mon Jul 04, 2016 12:33 pm #50179 Hello,

I'm trying to figure out the whole udp send/receive thing from Wemos/esp2866/arduino.io to max msp.

I started out with the ntp client example, from github because and here starts the madness. If I use the regular file that's in the examples in arduino then I get a compiling error on my Imac. When I use the one below from the github on my Imac it compiles and is ready to be uploaded in my WemosD1 Mini, but, my Imac has problems uploading the files on my wemos. Whereas my macbook pro does achieve this (with the same setting and such). But then my macbook doesn't compile the code and gives me following error.
ERROR:

WiFiUdpNtpClient.ino: In function 'void setup()':
WiFiUdpNtpClient:41: error: 'Serial' was not declared in this scope
WiFiUdpNtpClient.ino: In function 'void loop()':
WiFiUdpNtpClient:81: error: 'Serial' was not declared in this scope
WiFiUdpNtpClient.ino: In function 'void printWifiStatus()':
WiFiUdpNtpClient:159: error: 'Serial' was not declared in this scope


CODE:

Code: Select all/*

 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>

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

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());
}

void loop()
{
  //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(':');
    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
  }
  // 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();
}

SO, before I can even start figuring out the udp protocol and then how to send I2C data over it to max, I need this problem solved.

Need help!!

- Mon Jul 04, 2016 1:24 pm #50183 OK!!

Did what is best to do, rebuild the whole ide. And now no more compilling errors.

But in my console I get following:

�̤�!���H��b�


strange?

- Mon Jul 04, 2016 1:26 pm #50185

OK!!

Did what is best to do, rebuild the whole ide. And now no more compilling errors.

But in my console I get following:

�̤�!���H��b�


strange?

Baudrate is the same as in the script!

- Mon Jul 04, 2016 2:25 pm #50190 Hi, are the expected values outside the normal ASCII set. You might want Serial.write(); instead of Serial.print();