#define SENSOR_PIN 4   // ADC GPIO4
#define SENSITIVITY 185  // 185mV/A for 5A module (Change for your module)
#define ADC_RESOLUTION 4096  // 12-bit ADC (ESP32)
#define V_REF 3300  // ESP32 ADC Reference Voltage (mV)

const int numSamples = 100;  
float zeroPoint;  

void setup() {
    Serial.begin(115200);
    pinMode(SENSOR_PIN, INPUT);
    delay(2000);

    // Measure idle voltage (zero current)
    long sum = 0;
    for (int i = 0; i < numSamples; i++) {
        sum += analogReadMilliVolts(SENSOR_PIN);
        delay(10);
    }
    zeroPoint = sum / numSamples;
    Serial.print("Zero Point (No Current): ");
    Serial.print(zeroPoint);
    Serial.println(" mV");
}

float readACCurrent() {
    float sumSquared = 0;

    for (int i = 0; i < numSamples; i++) {
        float voltage = analogReadMilliVolts(SENSOR_PIN);  
        float current = (voltage - zeroPoint) / SENSITIVITY;  
        sumSquared += current * current;
        delay(1);
    }

    return sqrt(sumSquared / numSamples);  
}

void loop() {
    float acCurrent = readACCurrent();
    Serial.print("AC Current RMS: ");
    Serial.print(acCurrent, 3);
    Serial.println(" A");
    delay(1000);
}