RTC_NTPSync.ino

/**
 * This example shows how to set the RTC (Real Time Clock) on the Portenta C33 / UNO R4 WiFi
 * to the current date and time retrieved from an NTP server on the Internet (pool.ntp.org).
 * Then the current time from the RTC is printed to the Serial port.
 * 
 * Instructions:
 * 1. Download the NTPClient library (https://github.com/arduino-libraries/NTPClient) through the Library Manager
 * 2. Change the WiFi credentials in the arduino_secrets.h file to match your WiFi network.
 * 3. Upload this sketch to Portenta C33 / UNO R4 WiFi.
 * 4. Open the Serial Monitor.
 * 
 * Initial author: Sebastian Romero @sebromero
 */

#include "RTC.h"
#include <NTPClient.h>

#if defined(ARDUINO_PORTENTA_C33)
#include <WiFiC3.h>
#elif defined(ARDUINO_UNOWIFIR4)
#include <WiFiS3.h>
#endif

#include <WiFiUdp.h>
#include "arduino_secrets.h" 

///////please enter your sensitive data in the Secret tab/arduino_secrets.h
char ssid[] = SECRET_SSID;        // your network SSID (name)
char pass[] = SECRET_PASS;    // your network password (use for WPA, or use as key for WEP)

int wifiStatus = WL_IDLE_STATUS;
WiFiUDP Udp; // A UDP instance to let us send and receive packets over UDP
NTPClient timeClient(Udp);

void printWifiStatus() {
  // print the SSID of the network you're attached to:
  Serial.print("SSID: ");
  Serial.println(WiFi.SSID());

  // print your board's IP address:
  IPAddress ip = WiFi.localIP();
  Serial.print("IP Address: ");
  Serial.println(ip);

  // print the received signal strength:
  long rssi = WiFi.RSSI();
  Serial.print("signal strength (RSSI):");
  Serial.print(rssi);
  Serial.println(" dBm");
}

void connectToWiFi(){
  // check for the WiFi module:
  if (WiFi.status() == WL_NO_MODULE) {
    Serial.println("Communication with WiFi module failed!");
    // don't continue
    while (true);
  }

  String fv = WiFi.firmwareVersion();
  if (fv < WIFI_FIRMWARE_LATEST_VERSION) {
    Serial.println("Please upgrade the firmware");
  }

  // attempt to connect to WiFi network:
  while (wifiStatus != WL_CONNECTED) {
    Serial.print("Attempting to connect to SSID: ");
    Serial.println(ssid);
    // Connect to WPA/WPA2 network. Change this line if using open or WEP network:
    wifiStatus = WiFi.begin(ssid, pass);

    // wait 10 seconds for connection:
    delay(10000);
  }

  Serial.println("Connected to WiFi");
  printWifiStatus();
}

void setup(){
  Serial.begin(9600);
  while (!Serial);

  connectToWiFi();
  RTC.begin();
  Serial.println("\nStarting connection to server...");
  timeClient.begin();
  timeClient.update();

  // Get the current date and time from an NTP server and convert
  // it to UTC +2 by passing the time zone offset in hours.
  // You may change the time zone offset to your local one.
  auto timeZoneOffsetHours = 2;
  auto unixTime = timeClient.getEpochTime() + (timeZoneOffsetHours * 3600);
  Serial.print("Unix time = ");
  Serial.println(unixTime);
  RTCTime timeToSet = RTCTime(unixTime);
  RTC.setTime(timeToSet);

  // Retrieve the date and time from the RTC and print them
  RTCTime currentTime;
  RTC.getTime(currentTime); 
  Serial.println("The RTC was just set to: " + String(currentTime));
}

void loop(){}