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/*******************************************************************************
* Copyright (C) 2017 Maxim Integrated Products, Inc., All Rights Reserved.
*
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* OTHER DEALINGS IN THE SOFTWARE.
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* Products, Inc. Branding Policy.
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*******************************************************************************/

#ifndef MaximInterface_DS1920
#define MaximInterface_DS1920

#include <MaximInterface/Links/SelectRom.hpp>
#include <MaximInterface/Links/Sleep.hpp>
#include <MaximInterface/Utilities/array_span.hpp>
#include <MaximInterface/Utilities/Export.h>

namespace MaximInterface {

/// @brief DS1920 1-Wire Temperature iButton
/// @details The iButton® temperature logger (DS1920) provides
/// direct-to-digital 9-bit temperature readings over a range of
/// -55°C to +100°C in 0.5° increments. The iButton communicates with
/// a processor using the 1-Wire® protocol through a hardware port
/// interface. The port interface provides both the physical link and
/// handles the communication protocols that enable the processor to
/// access iButton resources with simple commands. Two bytes of
/// EEPROM can be used either to set alarm triggers or for storing
/// user data.
class DS1920 {
public:
  enum ErrorValue { CrcError = 1, DataError };

  /// Holds the contents of the device scratchpad.
  typedef array_span<uint_least8_t, 8> Scratchpad;

  DS1920(Sleep & sleep, OneWireMaster & master, const SelectRom & selectRom)
      : selectRom(selectRom), master(&master), sleep(&sleep) {}

  void setSleep(Sleep & sleep) { this->sleep = &sleep; }
  
  void setMaster(OneWireMaster & master) { this->master = &master; }
  
  void setSelectRom(const SelectRom & selectRom) {
    this->selectRom = selectRom;
  }

  /// @brief Write Scratchpad Command
  /// @details If the result of a temperature measurement is higher
  /// than TH or lower than TL, an alarm flag inside the device is
  /// set. This flag is updated with every temperature measurement.
  /// As long as the alarm flag is set, the DS1920 will respond to
  /// the alarm search command.
  /// @param[in] th 8-bit upper temperature threshold, MSB indicates sign.
  /// @param[in] tl 8-bit lower temperature threshold, MSB indicates sign.
  MaximInterface_EXPORT error_code writeScratchpad(uint_least8_t th,
                                                   uint_least8_t tl);

  /// @brief Read Scratchpad Command
  /// @param[out] scratchpad Contents of scratchpad.
  MaximInterface_EXPORT error_code readScratchpad(Scratchpad::span scratchpad);

  /// @brief Copy Scratchpad Command
  /// @details This command copies from the scratchpad into the
  /// EEPROM of the DS1920, storing the temperature trigger bytes
  /// in nonvolatile memory.
  MaximInterface_EXPORT error_code copyScratchpad();

  /// @brief Convert Temperature Command
  /// @details This command begins a temperature conversion.
  MaximInterface_EXPORT error_code convertTemperature();

  /// @brief Recall Command
  /// @details This command recalls the temperature trigger values
  /// stored in EEPROM to the scratchpad.
  MaximInterface_EXPORT error_code recallEeprom();

  MaximInterface_EXPORT static const error_category & errorCategory();

private:
  SelectRom selectRom;
  OneWireMaster * master;
  const Sleep * sleep;
};

/// @brief Reads the current temperature as an integer value.
/// @param ds1920 Device to read.
/// @param[out] temperature Temperature in degrees Celsius multiplied by 2.
MaximInterface_EXPORT error_code readTemperature(DS1920 & ds1920,
                                                 int & temperature);

inline error_code make_error_code(DS1920::ErrorValue e) {
  return error_code(e, DS1920::errorCategory());
}

} // namespace MaximInterface

#endif