/* * Net Keyboard * * Alistair MacDonald 2026 * */ #include #include #include #include "indexhtml.h" Wiznet55rp20lwIP ethernet(20); // Chip select on pin 20 // Create a [web] server object WiFiServer server(80); // Create a multicast DNS (mDNS) object WiFiUDP udp; MDNS mdns(udp); // The main setup routing void setup() { // Open the serial port for debuggin Serial.begin(115200); Serial.println(); Serial.println("Starting..."); // Initalise the Ethernet interface if (!ethernet.begin()) { Serial.println("Error: No Ethernet hardware detected."); while (true) { delay(1000); } } // Wait for connection and an IP address while (!ethernet.connected()) { Serial.print("."); delay(500); } // Report our IP address Serial.println(""); Serial.println("Ethernet connected"); Serial.println("IP address: "); Serial.println(ethernet.localIP()); // Initiate mDNS so we can be discovered mdns.begin(ethernet.localIP(), "netkeyboard"); // Enable the USB keyboard emulation Keyboard.begin(); // Start the [web] server server.begin(); } // A function to return the keybaord page void sendResponce_index(WiFiClient client) { client.println("HTTP/1.1 200 OK"); client.println("Content-Type: text/html"); client.println("Connection: close"); // the connection will be closed after completion of the response client.println(); client.println(indexHTML); } // A function to send a key pres from the emulatied USB keyboard void sendResponce_key(WiFiClient client, String inKey) { int keyCode = inKey.toInt(); if (keyCode>0) { Keyboard.write(keyCode); Serial.print("Keycode sent : "); Serial.println(keyCode); } else { Serial.print("Invalid keycode : "); Serial.println(inKey); } } // Send a 404 error page if an unexpected page is requested void sendResponce_404(WiFiClient client) { client.println("HTTP/1.1 404 Not Found"); client.println("Content-Type: text/html"); client.println("Connection: close"); // the connection will be closed after completion of the response client.println(); client.println(F("Not Found<title>

Not Found

The requested URL was not found on this server.

")); } // A helper function to read a string from a netowrk connection String readClientString(WiFiClient client) { String nextLine = ""; // Loop thougth reading a character at a time while ( client.connected() ) { char nextChar = client.read(); // Add character to the new string if not a control character if ( (nextChar>=32) && (nextChar<=126) ) { nextLine += nextChar; } // Return the completed string if complete else if (nextChar==10) { return nextLine; } // Ignore any control characters we don't knwo how to deal with } // Return what we have if the connection is closed while reading return nextLine; } // A function to service a web request connection void serviceConnection(WiFiClient client) { // Read the HTTP request String requestLine = readClientString(client); // Read the rest of the header while (client.connected()) { String headerLine = readClientString(client); if (headerLine=="") break; } // Send the responce if ( requestLine.startsWith("GET / ") ) { // The main page (with the keyboard on it) return sendResponce_index(client); } else if ( requestLine.startsWith("POST /key?code=") ) { // An api call to send a key press return sendResponce_key(client, requestLine.substring(15, requestLine.lastIndexOf(" "))); } else { // A error fallback for anything else return sendResponce_404(client); } } void loop() { // listen for incoming clients WiFiClient client = server.accept(); if (client) { Serial.println("New connection."); serviceConnection(client); // A qucik fix to give the web browser time to receive the data delay(100); // close the connection: client.stop(); } // Advertise ourselves to the local netowrk using mDNS mdns.run(); }