test server

Author: clockspot

test-server/test-server.ino

@@ -0,0 +1,98 @@
+#include <SPI.h>
+#include <WiFiNINA.h>
+#include <WiFiUdp.h>
+
+#include "secrets.h" //supply your own
+char ssid[] = SECRET_SSID; // your network SSID (name)
+char pass[] = SECRET_PASS; // your network password (use for WPA, or use as key for WEP)
+
+unsigned int localPort = 2395; // local port to listen for UDP packets
+IPAddress timeServer(129, 6, 15, 28); // time.nist.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
+WiFiUDP Udp; // A UDP instance to let us send and receive packets over UDP
+
+WiFiServer server(80);
+
+
+void setup() {
+  Serial.begin(9600);
+  while(!Serial); //only works on 33 IOT
+  startWiFi();
+}
+
+unsigned long millisLast = 0;
+void loop() {
+  //Every 5 seconds, make a UDP call to NTP
+  if(millis()-millisLast > 5000) { millisLast+=5000; startNTP(); }
+  //Every loop, check for a UDP response and a client connection
+  checkForNTPResponse();
+  checkForServerClients();
+}
+
+
+void startWiFi(){
+  if(WiFi.status()==WL_NO_MODULE) Serial.println("Communication with WiFi module failed!");
+  else if(WiFi.firmwareVersion()<WIFI_FIRMWARE_LATEST_VERSION) Serial.println("Please upgrade the firmware");
+  else { //hardware is ok
+    Serial.print(F("Attempting to connect to SSID: ")); Serial.println(ssid);
+    WiFi.begin(ssid, pass); //hangs while connecting
+    if(WiFi.status()==WL_CONNECTED){ //did it work?
+      Serial.println("Connected!");
+      Serial.print("SSID: "); Serial.println(WiFi.SSID());
+      Serial.print("IP address: "); Serial.println(WiFi.localIP());
+      Serial.print("Signal strength (RSSI):"); Serial.print(WiFi.RSSI()); Serial.println(" dBm");
+      server.begin();
+    } else { //it didn't work
+      Serial.println("Wasn't able to connect.");
+    } //end it didn't work
+  } //end hardware is ok
+} //end fn startWiFi
+
+bool ntpStartLast = 0;
+void startNTP(){ //Called at intervals to check for ntp time
+  if(WiFi.status()!=WL_CONNECTED) return;
+  if(ntpStartLast!=0 && millis()-ntpStartLast < 3000) return; //do not send more than one request within 3 seconds
+  Serial.println();
+  ntpStartLast = millis();
+  Udp.flush(); //does this do any good?
+  Udp.stop();
+  Serial.print(millis()); Serial.println(" Sending UDP packet to NTP server.");
+  Serial.print("Udp.begin: "); Serial.println(Udp.begin(localPort)); //open connection
+  memset(packetBuffer, 0, NTP_PACKET_SIZE); // set all bytes in the buffer to 0
+  // Initialize values needed to form NTP request
+  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;
+  Serial.print("Udp.beginPacket: "); Serial.println(Udp.beginPacket(timeServer, 123)); //NTP requests are to port 123
+  Udp.write(packetBuffer, NTP_PACKET_SIZE);
+  Serial.print("Udp.endPacket: "); Serial.println(Udp.endPacket());
+} //end fn startNTP
+
+void checkForNTPResponse(){ //Called on every cycle to see if there is an ntp response to handle
+  if(!ntpStartLast) return;
+  if(!Udp.parsePacket()) return;
+  // We've received a packet, read the data from it
+  Udp.read(packetBuffer, NTP_PACKET_SIZE); // read the packet into the buffer
+  unsigned long ntpTime = (packetBuffer[40] << 24) | (packetBuffer[41] << 16) | (packetBuffer[42] << 8) | packetBuffer[43];
+  Serial.print(millis()); Serial.print(" Received UDP packet from NTP server. Time is "); Serial.println(ntpTime);
+  Udp.stop();
+  ntpStartLast = 0;
+} //end fn checkNTP
+
+
+void checkForServerClients(){
+  if(WiFi.status()!=WL_CONNECTED) return;
+  WiFiClient client = server.available();
+  if(client){
+    Serial.println(); Serial.print(millis()); Serial.println(" Got client.");
+    client.flush(); //does this do any good?
+    client.stop();
+  }
+}