Fix RTC WiFi example

Author: Hannes7eicher

content/hardware/10.mega/boards/giga-r1-wifi/tutorials/giga-wifi/giga-wifi.md

@@ -156,117 +156,187 @@ void printMacAddress(byte mac[]) {
 
 ```arduino
 /*
- This example connects to an unencrypted WiFi network.
- Then it prints the MAC address of the WiFi module,
- the IP address obtained, and other network details.
+ Udp NTP Client
 
- Circuit:
- * GIGA R1 WiFi
+ 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 13 July 2010
- by dlf (Metodo2 srl)
- modified 31 May 2012
+ created 4 Sep 2010
+ by Michael Margolis
+ modified 9 Apr 2012
  by Tom Igoe
- modified 22 March 2023
- by Karl Söderby
- */
+ modified 28 Dec 2022
+ by Giampaolo Mancini
 
+This code is in the public domain.
+ */
 
-#include <SPI.h>
 #include <WiFi.h>
+#include <WiFiUdp.h>
+#include <mbed_mktime.h>
 
-#include "arduino_secrets.h" 
+int status = WL_IDLE_STATUS;
+#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 status = WL_IDLE_STATUS;     // the WiFi radio's status
+char ssid[] = ""; // your network SSID (name)
+char pass[] = ""; // your network password (use for WPA, or use as key for WEP)
+int keyIndex = 0; // your network key index number (needed only for WEP)
 
-void setup() {
-  //Initialize serial and wait for port to open:
-  Serial.begin(9600);
-  while (!Serial) {
-    ; // wait for serial port to connect. Needed for native USB port only
-  }
+unsigned int localPort = 2390; // local port to listen for UDP packets
 
-  // check for the WiFi module:
-  if (WiFi.status() == WL_NO_MODULE) {
-    Serial.println("Communication with WiFi module failed!");
-    // don't continue
-    while (true);
-  }
+// IPAddress timeServer(162, 159, 200, 123); // pool.ntp.org NTP server
 
-  // attempt to connect to WiFi network:
-  while (status != WL_CONNECTED) {
-    Serial.print("Attempting to connect to WPA SSID: ");
-    Serial.println(ssid);
-    // Connect to WPA/WPA2 network:
-    status = WiFi.begin(ssid, pass);
+constexpr auto timeServer { "pool.ntp.org" };
 
-    // wait 10 seconds for connection:
-    delay(10000);
-  }
+const int NTP_PACKET_SIZE = 48; // NTP timestamp is in the first 48 bytes of the message
 
-  // you're connected now, so print out the data:
-  Serial.print("You're connected to the network");
-  printCurrentNet();
-  printWifiData();
+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 loop() {
-  // check the network connection once every 10 seconds:
-  delay(10000);
-  printCurrentNet();
-}
+constexpr unsigned long printInterval { 1000 };
+unsigned long printNow {};
 
-void printWifiData() {
-  // print your board's IP address:
-  IPAddress ip = WiFi.localIP();
-  Serial.print("IP Address: ");
-  Serial.println(ip);
-  Serial.println(ip);
+void setup()
+{
+    // Open serial communications and wait for port to open:
+    Serial.begin(9600);
+    while (!Serial) {
+        ; // wait for serial port to connect. Needed for native USB port only
+    }
 
-  // print your MAC address:
-  byte mac[6];
-  WiFi.macAddress(mac);
-  Serial.print("MAC address: ");
-  printMacAddress(mac);
-}
+    // check for the WiFi module:
+    if (WiFi.status() == WL_NO_SHIELD) {
+        Serial.println("Communication with WiFi module failed!");
+        // don't continue
+        while (true)
+            ;
+    }
 
-void printCurrentNet() {
-  // print the SSID of the network you're attached to:
-  Serial.print("SSID: ");
-  Serial.println(WiFi.SSID());
+    // attempt to connect to WiFi network:
+    while (status != 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:
+        status = WiFi.begin(ssid, pass);
 
-  // print the MAC address of the router you're attached to:
-  byte bssid[6];
-  WiFi.BSSID(bssid);
-  Serial.print("BSSID: ");
-  printMacAddress(bssid);
+        // wait 10 seconds for connection:
+        delay(10000);
+    }
 
-  // print the received signal strength:
-  long rssi = WiFi.RSSI();
-  Serial.print("signal strength (RSSI):");
-  Serial.println(rssi);
+    Serial.println("Connected to WiFi");
+    printWifiStatus();
+
+    setNtpTime();
 
-  // print the encryption type:
-  byte encryption = WiFi.encryptionType();
-  Serial.print("Encryption Type:");
-  Serial.println(encryption, HEX);
-  Serial.println();
 }
 
-void printMacAddress(byte mac[]) {
-  for (int i = 5; i >= 0; i--) {
-    if (mac[i] < 16) {
-      Serial.print("0");
+void loop()
+{
+    if (millis() > printNow) {
+        Serial.print("System Clock:          ");
+        Serial.println(getLocaltime());
+        printNow = millis() + printInterval;
     }
-    Serial.print(mac[i], HEX);
-    if (i > 0) {
-      Serial.print(":");
+}
+
+void setNtpTime()
+{
+    Udp.begin(localPort);
+    sendNTPpacket(timeServer);
+    delay(1000);
+    parseNtpPacket();
+}
+
+// send an NTP request to the time server at the given address
+unsigned long sendNTPpacket(const char * address)
+{
+    memset(packetBuffer, 0, NTP_PACKET_SIZE);
+    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;
+
+    Udp.beginPacket(address, 123); // NTP requests are to port 123
+    Udp.write(packetBuffer, NTP_PACKET_SIZE);
+    Udp.endPacket();
+}
+
+unsigned long parseNtpPacket()
+{
+    if (!Udp.parsePacket())
+        return 0;
+
+    Udp.read(packetBuffer, NTP_PACKET_SIZE);
+    const unsigned long highWord = word(packetBuffer[40], packetBuffer[41]);
+    const unsigned long lowWord = word(packetBuffer[42], packetBuffer[43]);
+    const unsigned long secsSince1900 = highWord << 16 | lowWord;
+    constexpr unsigned long seventyYears = 2208988800UL;
+    const unsigned long epoch = secsSince1900 - seventyYears;
+    set_time(epoch);
+
+#if defined(VERBOSE)
+    Serial.print("Seconds since Jan 1 1900 = ");
+    Serial.println(secsSince1900);
+
+    // now convert NTP time into everyday time:
+    Serial.print("Unix time = ");
+    // 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.println();
+    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
+#endif
+
+    return epoch;
+}
+
+String getLocaltime()
+{
+    char buffer[32];
+    tm t;
+    _rtc_localtime(time(NULL), &t, RTC_FULL_LEAP_YEAR_SUPPORT);
+    strftime(buffer, 32, "%Y-%m-%d %k:%M:%S", &t);
+    return String(buffer);
+}
+
+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");
 }
 ```