DS3232RTC.h

/*
 * DS3232RTC.h - library for DS3232 RTC from Freetronics; http://www.freetronics.com/rtc
 * This library is intended to be used with Arduino Time.h library functions; http://playground.arduino.cc/Code/Time
 * Based on code by Jonathan Oxer at http://www.freetronics.com/pages/rtc-real-time-clock-module-quickstart-guide
 * Based on code by Michael Margolis at http://code.google.com/p/arduino-time
 * Based on code by Ryhs Weather at http://github.com/rweather/arduinolibs/tree/master/libraries/RTC

  Copyright (c) 2013 by the Arduino community (Author anonymous)

  This work is licensed under the Creative Commons ShareAlike 1.0 Generic (CC SA 1.0) License
  To view a copy of this license, visit http://creativecommons.org/licenses/sa/1.0 or send a
  letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.

  This library 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.
 */

#ifndef DS3232RTC_h
#define DS3232RTC_h

#include <stdint.h>
#include <Wire.h>    // http://arduino.cc/en/Reference/Wire
#include <Stream.h>  // http://arduino.cc/en/Reference/Stream
#include <TimeLib.h> // http://playground.arduino.cc/Code/time

// Based on page 11 of specs; http://www.maxim-ic.com/datasheet/index.mvp/id/4984
#define DS3232_I2C_ADDRESS 0x68

enum alarmMode_t {
  alarmModeUnknown,       // not in spec table
  alarmModePerSecond,     // once per second, A1 only
  alarmModePerMinute,     // once per minute, A2 only
  alarmModeSecondsMatch,  // when seconds match, A1 only
  alarmModeMinutesMatch,  // when minutes [and seconds] match
  alarmModeHoursMatch,    // when hours, minutes [and seconds] match
  alarmModeDateMatch,     // when date (of month), hours, minutes [and seconds] match
  alarmModeDayMatch,      // when day (of week), hours, minutes [and seconds] match
  alarmModeOff            // set to date or day, but value is 0
  };

enum sqiMode_t {
  sqiModeNone, 
  sqiMode1Hz, 
  sqiMode1024Hz, 
  sqiMode4096Hz, 
  sqiMode8192Hz, 
  sqiModeAlarm1, 
  sqiModeAlarm2, 
  sqiModeAlarmBoth
  };

enum tempScanRate_t {
  tempScanRate64sec,
  tempScanRate128sec,
  tempScanRate256sec,
  tempScanRate512sec
  };

typedef struct  { 
  int8_t Temp; 
  uint8_t Decimal; 
} tpElements_t, TempElements, *tpElementsPtr_t;

static const uint8_t NO_TEMPERATURE = 0x7F; 

// Helpers
#define temperatureCToF(C) (C * 9 / 5 + 32)
#define temperatureFToC(F) ((F - 32) * 5 / 9)

/**
 * DS3232RTC Class
 */
class DS3232RTC
{
  public:
    DS3232RTC();
    static bool available();
    // Date and Time
    static time_t get();
    static void set(time_t t);
    static void read(tmElements_t &tm);
    static void write(tmElements_t &tm);
    static void writeTime(tmElements_t &tm);
    static void writeDate(tmElements_t &tm);
    // Alarms
    static void readAlarm(uint8_t alarm, alarmMode_t &mode, tmElements_t &tm);
    static void writeAlarm(uint8_t alarm, alarmMode_t mode, tmElements_t tm);
    // Control Register
    static void setBBOscillator(bool enable);
    static void setBBSqareWave(bool enable);
    static void setSQIMode(sqiMode_t mode);
    static bool isAlarmInterupt(uint8_t alarm);
    // Control/Status Register
    static bool isOscillatorStopFlag();
    static void setOscillatorStopFlag(bool enable);
    static void setBB33kHzOutput(bool enable);
    static void setTCXORate(tempScanRate_t rate);
    static void set33kHzOutput(bool enable);
    static bool isTCXOBusy();
    static bool isAlarmFlag(uint8_t alarm);
    static uint8_t isAlarmFlag();
    static void clearAlarmFlag(uint8_t alarm);
    // Temperature
    static void readTemperature(tpElements_t &tmp);
  private:
    static uint8_t dec2bcd(uint8_t num);
    static uint8_t bcd2dec(uint8_t num);
  protected:
    static void _wTime(tmElements_t &tm);
    static void _wDate(tmElements_t &tm);
    static uint8_t read1(uint8_t addr);
    static void write1(uint8_t addr, uint8_t data);
};

extern DS3232RTC RTC;

/**
 * DS3232SRAM Class
 */
class DS3232SRAM : public Stream
{
  public:
    DS3232SRAM();
    // more like EEPROMClass
    static uint8_t read(int addr);
    static void write(int addr, uint8_t data);

    // from Print class
    #if ARDUINO >= 100
    virtual size_t write(uint8_t data);
    virtual size_t write(const char *str);
    virtual size_t write(const uint8_t *buf, size_t size);
    #else
    virtual void write(uint8_t);
    virtual void write(const char *str);
    virtual void write(const uint8_t *buf, size_t size);
    #endif

    // from Stream class
    virtual int available();
    virtual int read();
    virtual int peek();
    virtual void flush();  // Sets the next character position to 0.
    uint8_t seek(uint8_t pos);  // Sets the position of the next character to be extracted from the stream.
    uint8_t tell();  // Returns the position of the current character in the stream.

  private:
    bool _init;
    bool _avail;
    uint8_t _cursor;
};

extern DS3232SRAM SRAM;

#endif