VoltageReference.h

/*
 VoltageReference.cpp - VoltageReference library
 Copyright (c) 2014 Roberto Lo Giacco.
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Lesser General Public License as 
 published by the Free Software Foundation, either version 3 of the 
 License, or (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
#ifndef VOLTAGE_REFERENCE_H_
#define VOLTAGE_REFERENCE_H_
 
#include "Arduino.h"
 
#define ANALOG_MAX_VALUE 0x3FF
#define DEFAULT_REFERENCE_CALIBRATION 1126400L
#define INVALID_REFERENCE_CALIBRATION 0xFFFFFFL
 
#define getHiByte(calibration) (calibration >> 16)
#define getMidByte(calibration) (calibration >> 8)
#define getLowByte(calibration) (calibration & 0xFF)
#define mergeBytes(hi, mid, low) ((((long)hi) << 16) | ((mid << 8) | ((low & 0xFF) & 0xFFFF)))
 
class VoltageReference {
    private:
        uint32_t calibration;
 
        uint16_t readInternalRef();
    public:
 
        void begin(uint32_t reference = DEFAULT_REFERENCE_CALIBRATION);
 
        void begin(uint8_t hi, uint8_t mid, uint8_t low);
 
        uint16_t readVcc();
 
        uint32_t calibrate(uint16_t milliVolt);
 
        uint16_t internalValue();
 
};
#endif // VOLTAGE_REFERENCE_H_