// Arduino MCP79412RTC Library

// https://github.com/JChristensen/MCP79412RTC

// Copyright (C) 2018 by Jack Christensen and licensed under

// GNU GPL v3.0, https://www.gnu.org/licenses/gpl.html

//

// Arduino library for the Microchip MCP7941x Real-Time Clocks.

// Requires PJRC's improved version of the Arduino Time Library,

// https://playground.arduino.cc/Code/Time

// https://github.com/PaulStoffregen/Time

//

// For AVR architecture, an MCP79412RTC object named RTC is instantiated

// by the library and I2C initialization occurs in the constructor;

// this is for backwards compatibility.

// For other architectures, the user needs to instantiate a MCP79412RTC

// object and optionally initialize the I2C bus by calling

// MCP79412RTC::begin(). The constructor has an optional bool parameter

// to indicate whether I2C initialization should occur in the

// constructor; this parameter defaults to true if not given.

#ifndef MCP79412RTC_H_INCLUDED

#define MCP79412RTC_H_INCLUDED

#include <Arduino.h>

#include <TimeLib.h> // https://github.com/PaulStoffregen/Time

// Alarm types for use with the enableAlarm() function

enum {

ALM_MATCH_SECONDS,

ALM_MATCH_MINUTES,

ALM_MATCH_HOURS,

ALM_MATCH_DAY, // triggers alarm at midnight

ALM_MATCH_DATE,

ALM_RESERVED_5, // do not use

ALM_RESERVED_6, // do not use

ALM_MATCH_DATETIME,

ALM_DISABLE

};

// Square-wave output frequencies for use with squareWave() function

enum {

SQWAVE_1_HZ,

SQWAVE_4096_HZ,

SQWAVE_8192_HZ,

SQWAVE_32768_HZ,

SQWAVE_NONE

};

// constants for use with alarm functions

#define ALARM_0 0

#define ALARM_1 1

class MCP79412RTC

{

public:

MCP79412RTC(bool initI2C = true);

void begin();

static time_t get();

static void set(time_t t);

static bool read(tmElements_t &tm);

static void write(tmElements_t &tm);

void sramWrite(byte addr, byte value);

void sramWrite(byte addr, byte *values, byte nBytes);

byte sramRead(byte addr);

void sramRead(byte addr, byte *values, byte nBytes);

void eepromWrite(byte addr, byte value);

void eepromWrite(byte addr, byte *values, byte nBytes);

byte eepromRead(byte addr);

void eepromRead(byte addr, byte *values, byte nBytes);

int calibRead();

void calibWrite(int value);

void idRead(byte *uniqueID);

void getEUI64(byte *uniqueID);

bool powerFail(time_t *powerDown, time_t *powerUp);

void squareWave(uint8_t freq);

void setAlarm(uint8_t alarmNumber, time_t alarmTime);

void enableAlarm(uint8_t alarmNumber, uint8_t alarmType);

bool alarm(uint8_t alarmNumber);

void out(bool level);

void alarmPolarity(bool polarity);

bool isRunning();

void vbaten(bool enable);

private:

static void ramWrite(byte addr, byte value);

static void ramWrite(byte addr, byte *values, byte nBytes);

static byte ramRead(byte addr);

static void ramRead(byte addr, byte *values, byte nBytes);

static byte eepromWait();

static uint8_t dec2bcd(uint8_t num);

static uint8_t bcd2dec(uint8_t num);

};

#if defined ARDUINO_ARCH_AVR

extern MCP79412RTC RTC;

#endif

#ifndef _BV

#define _BV(bit) (1 << (bit))

#endif

#ifndef BUFFER_LENGTH // a horrible and limiting kludge for samd (arduino zero)

#define BUFFER_LENGTH 32

#endif

#endif