Instrumentos Virtuales
Arduino UNO + HMI Web

// =============================================
// Instrumento Virtual — Firmware base
// Arduino UNO + HMI Web via USB Serial
// =============================================

const int BAUD_RATE   = 115200;
const int SAMPLE_PIN  = A0;       // Pin analógico de entrada
const int LED_PIN     = 13;       // LED integrado

unsigned long lastSample   = 0;
unsigned long sampleRate   = 100;  // ms entre muestras
bool          streaming    = false;

String        inputBuffer  = "";   // Buffer para comandos entrantes

void setup() {
  Serial.begin(BAUD_RATE);
  pinMode(LED_PIN, OUTPUT);
  
  // Esperar a que el puerto serie esté listo
  while (!Serial) { delay(10); }
  
  // Mensaje de identificación al conectar
  Serial.println("HELLO:v1.0");
}

void loop() {
  readCommands();   // Procesar comandos entrantes
  sendSamples();    // Enviar datos si streaming activo
}

void sendSamples() {
  if (!streaming) return;
  
  unsigned long now = millis();
  if (now - lastSample < sampleRate) return;
  lastSample = now;

  // Leer canal analógico (0 a 1023)
  int raw = analogRead(SAMPLE_PIN);

  // Convertir a tensión (0.0 – 5.0 V)
  float voltage = raw * (5.0 / 1023.0);
  
  // Enviar en formato CLAVE:VALOR
  Serial.print("V0:");   Serial.println(raw);
  Serial.print("VV:");   Serial.println(voltage, 3);
}

void readCommands() {
  while (Serial.available() > 0) {
    char c = (char) Serial.read();
    
    if (c == '\n') {
      inputBuffer.trim();          // Eliminar \r y espacios
      if (inputBuffer.length() > 0) {
        interpretCommand(inputBuffer);
      }
      inputBuffer = "";            // Limpiar buffer
    } else {
      inputBuffer += c;           // Acumular caracteres
    }
  }
}

void interpretCommand(String cmd) {
  int sep = cmd.indexOf(':');
  String key   = (sep > 0) ? cmd.substring(0, sep) : cmd;
  String param = (sep > 0) ? cmd.substring(sep + 1) : "";

  if (key == "START") {
    streaming = true;
    Serial.println("OK");
  } else if (key == "STOP") {
    streaming = false;
    Serial.println("OK");
  } else if (key == "RATE") {
    sampleRate = param.toInt();
    Serial.println("OK");
  } else if (key == "LED") {
    digitalWrite(LED_PIN, param.toInt() ? HIGH : LOW);
    Serial.println("OK");
  } else if (key == "PWM") {
    analogWrite(9, param.toInt());
    Serial.println("OK");
  } else {
    Serial.print("ERR:CMD_UNKNOWN:");
    Serial.println(key);
  }
}