Subversion Repositories idreammicro-avr

/**************************************************************************//**

 * \brief DS1307 RTC library

 * \author Copyright (C) 2009  Julien Le Sech - www.idreammicro.com

 * \version 1.0

 * \date 20090501

 *

 * This file is part of the iDreamMicro library.

 *

 * This library 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 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. See the GNU Lesser General Public License for more

 * details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program. If not, see http://www.gnu.org/licenses/

 ******************************************************************************/

/**************************************************************************//**

 * \file ds1307.c

 ******************************************************************************/

/******************************************************************************

 * Header file inclusions.

 ******************************************************************************/

#include <ds1307/ds1307.h>

#include <twi/twi.h>

#include <useful/bits.h>

#include <useful/datetime.h>

#include <avr/io.h>

#include <assert.h>

#include <stdbool.h>

#include <stdlib.h>

/******************************************************************************

 * Private macros.

 ******************************************************************************/

#define DS1307__ADDRESS     0xD0

#define DS1307__REG_SECONDS     0x00

#define DS1307__REG_MINUTES 0x01

#define DS1307__REG_HOURS   0x02

#define DS1307__REG_DAY     0x03

#define DS1307__REG_DATE    0x04

#define DS1307__REG_MONTH   0x05

#define DS1307__REG_YEAR    0x06

#define DS1307__REG_CONTROL 0x07

#define DS1307__RS0         0x00

#define DS1307__RS1         0x01

#define DS1307__SQWE        0x04

#define DS1307__OUT         0x07

/**************************************************************************//**

 * \def     DS1307__REG_RAM

 * \brief   Start address of RAM registers (locations 0x08 to 0x3F).

 ******************************************************************************/

#define DS1307__REG_RAM       0x08

/******************************************************************************

 * Public function definitions.

 ******************************************************************************/

/**************************************************************************//**

 * \fn void ds1307__initialize(void)

 *

 * \brief Initialize RTC.

 ******************************************************************************/

void

ds1307__initialize

(

    void

){

    // We don't initialize TWI here: we may have several devices on the bus.

    // Initialize TWI.

    //twi__initialize(DS1307__CLOCK_RATE);

}

/**************************************************************************//**

 * \fn void ds1307__get_time(

 * date_time__time_t*   p_time,

 * ds1307__hour_mode_t* p_hour_mode)

 *

 * \brief Get RTC time.

 *

 * \param p_time a pointer to fill with RTC time

 * \param p_hour_mode a pointer to fill with RTC hour mode

 ******************************************************************************/

void

ds1307__get_time

(

    datetime__time_t*      p_time,

    ds1307__hour_mode_t*    p_hour_mode

){

    // Check the preconditions.

    assert(NULL != p_time);

    assert(NULL != p_hour_mode);

    twi__start();

    twi__send_slaw(DS1307__ADDRESS);

    twi__send_data(DS1307__REG_SECONDS);

    twi__stop();

    twi__start();

    twi__send_slar(DS1307__ADDRESS);

    uint8_t seconds = 0;

    twi__receive_data_ack(&seconds);

    uint8_t minutes = 0;

    twi__receive_data_ack(&minutes);

    uint8_t hours = 0;

    twi__receive_data_nack(&hours);

    p_time->seconds = (((seconds & 0x70) >> 4) * 10) + (seconds & 0x0F);

    p_time->minutes = (((minutes & 0x70) >> 4) * 10) + (minutes & 0x0F);

    *p_hour_mode = (ds1307__hour_mode_t)((hours & 0x40) >> 6);

    if (DS1307__HOUR_MODE__12_HOUR == *p_hour_mode)

    {

        p_time->meridiem = (datetime__meridiem_t)((hours & 0x20) >> 5);

        p_time->hours = (((hours & 0x10) >> 4) * 10) + (hours & 0x0F);

    }

    else

    {

        p_time->hours = (((hours & 0x30) >> 4) * 10) + (hours & 0x0F);

    }

    twi__stop();

}

/**************************************************************************//**

 * \fn void ds1307__set_time(

 * date_time__time_t* p_time,

 * ds1307__hour_mode_t hour_mode)

 *

 * \brief Set RTC time.

 *

 * \param p_time time to set. p_time->meridiem isn't used in 12-hour mode.

 * \param hour_mode hour mode

 ******************************************************************************/

void

ds1307__set_time

(

    datetime__time_t*  p_time,

    ds1307__hour_mode_t hour_mode

){

    // Check the preconditions.

    assert(NULL != p_time);

    twi__start();

    twi__send_slaw(DS1307__ADDRESS);

    twi__send_data(DS1307__REG_SECONDS);

    uint8_t seconds = ((p_time->seconds / 10) << 4) + (p_time->seconds % 10);

    uint8_t minutes = ((p_time->minutes / 10) << 4) + (p_time->minutes % 10);

    uint8_t hours = 0;

    if (DS1307__HOUR_MODE__12_HOUR == hour_mode)

    {

        hours = (hour_mode << 6) + (p_time->meridiem << 5)

            + ((p_time->hours / 10) << 4) + (p_time->hours % 10);

    }

    else

    {

        hours = (hour_mode << 6) + ((p_time->hours / 10) << 4)

            + (p_time->hours % 10);

    }

    twi__send_data(seconds);

    twi__send_data(minutes);

    twi__send_data(hours);

    twi__stop();

}

/**************************************************************************//**

 * \fn void ds1307__get_date(date_time__date_t* p_date)

 *

 * \brief Get RTC date.

 *

 * \param p_date a pointer to fill with RTC date

 ******************************************************************************/

void

ds1307__get_date

(

    datetime__date_t* p_date

){

    // Check the preconditions.

    assert(NULL != p_date);

    twi__start();

    twi__send_slaw(DS1307__ADDRESS);

    twi__send_data(DS1307__REG_DAY);

    twi__stop();

    twi__start();

    twi__send_slar(DS1307__ADDRESS);

    uint8_t day = 0;

    twi__receive_data_ack(&day);

    uint8_t date = 0;

    twi__receive_data_ack(&date);

    uint8_t month = 0;

    twi__receive_data_ack(&month);

    uint8_t year = 0;

    twi__receive_data_nack(&year);

    p_date->day = day;

    p_date->date = (((date & 0x30) >> 4) * 10) + (date & 0x0F);

    p_date->month = (((month & 0x10) >> 4) * 10) + (month & 0x0F);

    p_date->year = (((year & 0xF0) >> 4) * 10) + (year & 0x0F);

    twi__stop();

}

/**************************************************************************//**

 * \fn void ds1307__set_date(date_time__date_t* p_date)

 *

 * \brief Set RTC date.

 *

 * \param p_date date to set

 ******************************************************************************/

void

ds1307__set_date

(

    datetime__date_t* p_date

){

    // Check the preconditions.

    assert(NULL != p_date);

    twi__start();

    twi__send_slaw(DS1307__ADDRESS);

    twi__send_data(DS1307__REG_DAY);

    uint8_t date = ((p_date->date / 10) << 4) + (p_date->date % 10);

    uint8_t month = ((p_date->month / 10) << 4) + (p_date->month % 10);

    uint8_t year = ((p_date->year / 10) << 4) + (p_date->year % 10);

    twi__send_data(p_date->day);

    twi__send_data(date);

    twi__send_data(month);

    twi__send_data(year);

    twi__stop();

}

/**************************************************************************//**

 * \fn void ds1307__set_square_wave_output_level(ds1307__sqw_out_level_t level)

 *

 * \brief Set square wave output pin level.

 *

 * \param level Level to set.

 ******************************************************************************/

void

ds1307__set_square_wave_output_level

(

    ds1307__sqw_out_level_t level

){

    twi__start();

    twi__send_slaw(DS1307__ADDRESS);

    twi__send_data(DS1307__REG_CONTROL);

    uint8_t register_value = (level == DS1307__SQW_LEVEL__LOW) ? 0x00 : 0x80;

    twi__send_data(register_value);

    twi__stop();

}

/**************************************************************************//**

 * \fn void ds1307__set_square_wave_output_signal(

 * ds1307__sqw_out__frequency_t    frequency,

 * bool                            enable)

 *

 * \brief Set Square-Wave output signal.

 *

 * \param   frequency   Frequency.

 * \param   enable      Status.

 ******************************************************************************/

void

ds1307__set_square_wave_output_signal

(

    ds1307__sqw_out__frequency_t    frequency,

    bool                            enable

){

    uint8_t register_value = 0;

    // Rate select.

    switch (frequency)

    {

        case DS1307__SQW_FREQUENCY__4096_HZ:

            register_value = _BV(DS1307__RS0);

            break;

        case DS1307__SQW_FREQUENCY__8192_HZ:

            register_value = _BV(DS1307__RS1);

            break;

        case DS1307__SQW_FREQUENCY__32768_HZ:

            register_value = _BV(DS1307__RS1) | _BV(DS1307__RS0);

            break;

        case DS1307__SQW_FREQUENCY__1_HZ:

        default:

            register_value = 0;

            break;

    }

    // Square-Wave enable.

    if (enable)

    {

        BIT__SET(register_value, DS1307__SQWE);

    }

    twi__start();

    twi__send_slaw(DS1307__ADDRESS);

    twi__send_data(DS1307__REG_CONTROL);

    twi__send_data(register_value);

    twi__stop();

}