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

// -----------------------------------------------------------------------------
// Abstract sensor class (other sensor classes extend this class)
// Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
// -----------------------------------------------------------------------------

#pragma once

#include <Arduino.h>
#include <ArduinoJson.h>

typedef enum magnitude_t {

    MAGNITUDE_NONE = 0,

    MAGNITUDE_TEMPERATURE,
    MAGNITUDE_HUMIDITY,
    MAGNITUDE_PRESSURE,

    MAGNITUDE_CURRENT,
    MAGNITUDE_VOLTAGE,
    MAGNITUDE_POWER_ACTIVE,
    MAGNITUDE_POWER_APPARENT,
    MAGNITUDE_POWER_REACTIVE,
    MAGNITUDE_ENERGY,
    MAGNITUDE_ENERGY_DELTA,
    MAGNITUDE_POWER_FACTOR,

    MAGNITUDE_ANALOG,
    MAGNITUDE_DIGITAL,
    MAGNITUDE_EVENTS,

    MAGNITUDE_PM1dot0,
    MAGNITUDE_PM2dot5,
    MAGNITUDE_PM10,

    MAGNITUDE_CO2,

    MAGNITUDE_MAX,

} magnitude_t;

#define GPIO_NONE                   0x99

#define SENSOR_ERROR_OK             0       // No error
#define SENSOR_ERROR_OUT_OF_RANGE   1       // Result out of sensor range
#define SENSOR_ERROR_WARM_UP        2       // Sensor is warming-up
#define SENSOR_ERROR_TIMEOUT        3       // Response from sensor timed out
#define SENSOR_ERROR_UNKNOWN_ID     4       // Sensor did not report a known ID
#define SENSOR_ERROR_CRC            5       // Sensor data corrupted
#define SENSOR_ERROR_I2C            6       // Wrong or locked I2C address

class BaseSensor {

    public:

        // Constructor
        BaseSensor() {}

        // Destructor
        ~BaseSensor() {}

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

        // Loop-like method, call it in your main loop
        virtual void tick() {}

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

        // Post-read hook (usually to reset things)
        virtual void post() {}

        // Descriptive name of the sensor
        virtual String description() {}

        // Type for slot # index
        virtual magnitude_t type(unsigned char index) {}

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

        // Retrieve current instance configuration
        virtual void getConfig(JsonObject& root) {};

        // Save current instance configuration
        virtual void setConfig(JsonObject& root) {};

        // Load the configuration manifest
        static void manifest(JsonArray& root) {};

        // Descriptive name of the slot # index
        String slot(unsigned char index) { return description(); }

        // Sensor ID
        unsigned char getID() { return _sensor_id; };

        // Specific for I2C sensors
        unsigned char lock_i2c(unsigned char address, size_t size, unsigned char * addresses) {

            // Check if we should release a previously locked address
            if (_previous_address != address) {
                i2cReleaseLock(_previous_address);
            }

            // If we have already an address, check it is not locked
            if (address && !i2cGetLock(address)) {
                _error = SENSOR_ERROR_I2C;

            // If we don't have an address...
            } else {

                // Trigger auto-discover
                address = i2cFindAndLock(size, addresses);

                // If still nothing exit with error
                if (address == 0) _error = SENSOR_ERROR_I2C;

            }

            _previous_address = address;
            return address;

        }

        // Return sensor status (true for ready)
        bool status() { return _error == 0; }

        // Return sensor last internal error
        int error() { return _error; }

        // Number of available slots
        unsigned char count() { return _count; }

    protected:

        // Check if valid GPIO
        bool _validGPIO(unsigned char gpio) {
            if (0 <= gpio && gpio <= 5) return true;
            if (12 <= gpio && gpio <= 15) return true;
            return false;
        }

        unsigned char _sensor_id = 0x00;
        int _error = 0;
        bool _dirty = true;
        unsigned char _count = 0;

        // I2C
        unsigned char _previous_address = 0;
        unsigned char _address = 0;

};