R3ArduinoAd8317

void setup() {
  // 1. Standard R3 keyword for the AREF pin
  analogReference(EXTERNAL); 
  
  // Note: R3 does not support analogReadResolution, it is always 10-bit.

  Serial.begin(9600);
  delay(1000);
  Serial.println("--- ARDUINO R3: STABLE TRIAL MODE ---");
}

void loop() {
  long rangeCount = 5000; 
  float vOutSum = 0;
  float VoutMin = 3.3; 

  for (int i = 0; i < rangeCount; i++) {
    int rawValue = analogRead(A0);
    
    // 2. R3 MATH: Divide by 1024.0 (10-bit resolution)
    float vOut = (rawValue * 3.3) / 1024.0;

    if (vOut < VoutMin && vOut > 0.1) {
      VoutMin = vOut; 
    }
    vOutSum += vOut;
  }

  float VoutAverage = vOutSum / rangeCount;

  // AD8317 Logic
  float intercept = 2.0; 
  float slope = -0.022; 
  float dBm = (VoutMin - intercept) / slope;

  // 3. Printing results
  Serial.print("Avg: ");
  Serial.print(VoutAverage, 3); // R3 is accurate to 3 decimals
  Serial.print("V | Peak: ");
  Serial.print(VoutMin, 3);
  Serial.print("V | Power: ");
  Serial.print(dBm, 1);
  Serial.println(" dBm");

  delay(500); 
}