adc.h

// Class for a ADC chip or board
// Copyright (C) 2018 Carlos Kometter 
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU 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 <https://www.gnu.org/licenses/>.

#ifndef ADC_h_
#define ADC_h_

#include "Arduino.h"
#include "SPI.h"
#include "utils.h"

typedef unsigned char byte;

class AdcSpi {
 private:
  // sync_pin_ identifies the adc chip; each chip has a unique sync_pin_.
  // spi_bus_config_pin_ identifies the bus configurations.
  // More than one adc can share the same bus if they use the same spi configs.
  uint8_t sync_pin_, spi_bus_config_pin_, data_ready_pin_, spi_mode_;
  uint8_t clock_divider_;  // For due frequency = 84 MHz / clock_divider_
  BitOrder bit_order_;  // MSBFIRST or LSBFIRST
  uint8_t bit_resolution_;
  uint8_t reset_pin_;
 public:
  AdcSpi(void) = default;
  AdcSpi(uint8_t sync_pin, uint8_t spi_bus_config_pin,
     uint8_t data_ready_pin, uint8_t bit_resolution,
     uint8_t reset_pin=0, uint8_t clock_divider=7,
     BitOrder bit_order=MSBFIRST, uint8_t spi_mode=SPI_MODE3);
  bool Begin(void);
  double ReadVoltage(uint8_t channel=0);
  uint8_t ReadVoltage(uint8_t channel, byte previous_meas[], bool send);
 protected:
  virtual double BytesToVoltage(spi_utils::Message message) = 0;
  virtual spi_utils::Message SingleConversionModeMessage(uint8_t channel=0) = 0;
  virtual spi_utils::Message ReadDataRegisterMessage(uint8_t channel=0) = 0;
};
#endif