mhsw-espurna/code/espurna/sensors/EmonAnalogSensor.h

// -----------------------------------------------------------------------------
// Energy Monitor Sensor using builtin ADC
// Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
// -----------------------------------------------------------------------------

#pragma once

#include "Arduino.h"
#include "EmonSensor.h"

#define EMON_ANALOG_RESOLUTION      10
#define EMON_ANALOG_CHANNELS        1

class EmonAnalogSensor : public EmonSensor {

    public:

        // ---------------------------------------------------------------------
        // Public
        // ---------------------------------------------------------------------

        EmonAnalogSensor(): EmonSensor() {
            _channels = EMON_ANALOG_CHANNELS;
            _sensor_id = SENSOR_EMON_ANALOG_ID;
            init();
        }

        // ---------------------------------------------------------------------
        // Sensor API
        // ---------------------------------------------------------------------

        // Initialization method, must be idempotent
        void begin() {

            if (!_dirty) return;
            _dirty = false;

            // Number of slots
            _count = _magnitudes;

            // Bit depth
            _resolution = EMON_ANALOG_RESOLUTION;

            // Init analog PIN)
            pinMode(0, INPUT);

            // Call the parent class method
            EmonSensor::begin();

            // warmup channel 0 (the only one)
            read(0);

        }

        // Descriptive name of the sensor
        String description() {
            return String("EMON @ ANALOG @ GPIO0");
        }

        // Type for slot # index
        magnitude_t type(unsigned char index) {
            _error = SENSOR_ERROR_OK;
            unsigned char i=0;
            #if EMON_REPORT_CURRENT
                if (index == i++) return MAGNITUDE_CURRENT;
            #endif
            #if EMON_REPORT_POWER
                if (index == i++) return MAGNITUDE_POWER_APPARENT;
            #endif
            #if EMON_REPORT_ENERGY
                if (index == i) return MAGNITUDE_ENERGY;
            #endif
            _error = SENSOR_ERROR_OUT_OF_RANGE;
            return MAGNITUDE_NONE;
        }

        // Pre-read hook (usually to populate registers with up-to-date data)
        void pre() {

            _current[0] = read(0);

            #if EMON_REPORT_ENERGY
                static unsigned long last = 0;
                if (last > 0) {
                    _energy[0] += (_current[0] * _voltage * (millis() - last) / 1000);
                }
                last = millis();
            #endif

        }

        // Current value for slot # index
        double value(unsigned char index) {

            _error = SENSOR_ERROR_OK;
            unsigned char channel = index / _magnitudes;

            unsigned char i=0;
            #if EMON_REPORT_CURRENT
                if (index == i++) return _current[channel];
            #endif
            #if EMON_REPORT_POWER
                if (index == i++) return _current[channel] * _voltage;
            #endif
            #if EMON_REPORT_ENERGY
                if (index == i) return _energy[channel];
            #endif

            _error = SENSOR_ERROR_OUT_OF_RANGE;
            return 0;

        }

    protected:

        unsigned int readADC(unsigned char channel) {
            (void) channel;
            return analogRead(0);
        }

};