File content as of revision 17:c12eab714b4e:

/******************************************************************//**
* Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Except as contained in this notice, the name of Maxim Integrated
* Products, Inc. shall not be used except as stated in the Maxim Integrated
* Products, Inc. Branding Policy.
*
* The mere transfer of this software does not imply any licenses
* of trade secrets, proprietary technology, copyrights, patents,
* trademarks, maskwork rights, or any other form of intellectual
* property whatsoever. Maxim Integrated Products, Inc. retains all
* ownership rights.
**********************************************************************/


#include "ds3231.h"


#define DS3231_I2C_ADRS 0x68 
#define I2C_WRITE 0
#define I2C_READ  1

#define AM_PM     (1 << 5) 
#define MODE      (1 << 6)
#define DY_DT     (1 << 6)
#define ALRM_MASK (1 << 7)

//control register bit masks
#define A1IE  (1 << 0)
#define A2IE  (1 << 1)
#define INTCN (1 << 2)
#define RS1   (1 << 3)
#define RS2   (1 << 4)
#define CONV  (1 << 5)
#define BBSQW (1 << 6)
#define EOSC  (1 << 7)

//status register bit masks
#define A1F     (1 << 0)
#define A2F     (1 << 1)
#define BSY     (1 << 2)
#define EN32KHZ (1 << 3)
#define OSF     (1 << 7)


//*********************************************************************
Ds3231::Ds3231(PinName sda, PinName scl) 
:_p_i2c(new I2C(sda, scl)), _i2c_owner(true), _w_adrs((DS3231_I2C_ADRS << 1) | I2C_WRITE), 
_r_adrs((DS3231_I2C_ADRS << 1) | I2C_READ)
{
}


//*********************************************************************
Ds3231::Ds3231(I2C & i2c_bus)
:_p_i2c(&i2c_bus), _i2c_owner(false), _w_adrs((DS3231_I2C_ADRS << 1) | I2C_WRITE), 
_r_adrs((DS3231_I2C_ADRS << 1) | I2C_READ)
{
}


//*********************************************************************
Ds3231::~Ds3231()
{
    if(_i2c_owner)
    {
        delete _p_i2c;
    }
}


//*********************************************************************
uint16_t Ds3231::set_time(ds3231_time_t time)
{
    uint8_t data[] = {0,0,0,0};
    uint8_t data_length = 0;
    uint8_t max_hour = 24;
    
    data[data_length++] = SECONDS;
    data[data_length++] = uchar_2_bcd(time.seconds);
    data[data_length++] = uchar_2_bcd(time.minutes);
    
    //format Hours register
    data[data_length] = uchar_2_bcd(time.hours);
    if(time.mode)
    {
        max_hour = max_hour/2;
        
        data[data_length] |= MODE;
        if(time.am_pm)
        {
            data[data_length] |= AM_PM;
        }
        
    }
    else
    {
        max_hour = max_hour - 1;
    }
    data_length++;
    
    //Make sure data is within range.  
    if((time.seconds > 59) || (time.minutes > 59) || (time.hours > max_hour))
    {
        return(1);
    }
    else
    {
        return(_p_i2c->write(_w_adrs,(const char*) data, data_length));
    }
}


//*********************************************************************
uint16_t Ds3231::set_calendar(ds3231_calendar_t calendar)
{
    uint8_t data[] = {0,0,0,0,0};
    uint8_t data_length = 0;
    
    data[data_length++] = DAY;
    data[data_length++] = uchar_2_bcd(calendar.day);
    data[data_length++] = uchar_2_bcd(calendar.date);
    data[data_length++] = uchar_2_bcd(calendar.month);
    data[data_length++] = uchar_2_bcd(calendar.year);

    //Make sure data is within range.  
    if(((calendar.day < 1) || (calendar.day > 7)) || 
       ((calendar.date < 1) || (calendar.date > 31)) || 
       ((calendar.month < 1) || (calendar.month > 12)) || 
       (calendar.year > 99))
    {
        return(1);
    }
    else
    {
        return(_p_i2c->write(_w_adrs,(const char*) data, data_length));
    }
}


//*********************************************************************
uint16_t Ds3231::set_alarm(ds3231_alrm_t alarm, bool one_r_two)
{
    uint8_t data[] = {0,0,0,0,0};
    uint8_t data_length = 0;
    uint8_t max_hour = 24;
    uint8_t mask_var = 0;
    
    //setting alarm 1 or 2?
    if(one_r_two)
    {
        data[data_length++] = ALRM1_SECONDS;
        
        //config seconds register
        if(alarm.am1)
        {
           mask_var |= ALRM_MASK;
        }
        data[data_length++] =  (mask_var | uchar_2_bcd(alarm.seconds));
        mask_var = 0;
        
        //config minutes register
        if(alarm.am2)
        {
           mask_var |= ALRM_MASK;
        }
        data[data_length++] =  (mask_var | uchar_2_bcd(alarm.minutes));
        mask_var = 0;
        
        //config hours register
        if(alarm.am3)
        {
           mask_var |= ALRM_MASK;
        }
        if(alarm.mode)
        {
            max_hour = max_hour/2;
            mask_var |= MODE;
            if(alarm.am_pm)
            {
                mask_var |= AM_PM;
            }
        } 
        else
        {
            max_hour = max_hour - 1;
        }
        data[data_length++] =  (mask_var | uchar_2_bcd(alarm.hours));
        mask_var = 0;
        
        //config day/date register
        if(alarm.am4)
        {
           mask_var |= ALRM_MASK;
        }
        if(alarm.dy_dt)
        {
            mask_var |= DY_DT;
            data[data_length++] =  (mask_var | uchar_2_bcd(alarm.day));
        } 
        else
        {
            data[data_length++] =  (mask_var | uchar_2_bcd(alarm.date));
        }
        mask_var = 0;
    }
    else
    {
        data[data_length++] = ALRM2_MINUTES;
        
        //config minutes register
        if(alarm.am2)
        {
           mask_var |= ALRM_MASK;
        }
        data[data_length++] =  (mask_var | uchar_2_bcd(alarm.minutes));
        mask_var = 0;
        
        //config hours register
        if(alarm.am3)
        {
           mask_var |= ALRM_MASK;
        }
        if(alarm.mode)
        {
            max_hour = max_hour/2;
            mask_var |= MODE;
            if(alarm.am_pm)
            {
                mask_var |= AM_PM;
            }
        } 
        else
        {
            max_hour = max_hour - 1;
        }
        data[data_length++] =  (mask_var | uchar_2_bcd(alarm.hours));
        mask_var = 0;
        
        //config day/date register
        if(alarm.am4)
        {
           mask_var |= ALRM_MASK;
        }
        if(alarm.dy_dt)
        {
            mask_var |= DY_DT;
            data[data_length++] =  (mask_var | uchar_2_bcd(alarm.day));
        } 
        else
        {
            data[data_length++] =  (mask_var | uchar_2_bcd(alarm.date));
        }
        mask_var = 0;
    }  
    
    //Make sure data is within range.
    if((alarm.seconds > 59) || (alarm.minutes > 59) || (alarm.hours > max_hour) || 
       ((alarm.day < 1) || (alarm.day > 7)) || 
       ((alarm.date < 1) || (alarm.date > 31)))
    {
        return(1);
    }
    else
    {
        return(_p_i2c->write(_w_adrs,(const char*) data, data_length));
    }
}


//*********************************************************************
uint16_t Ds3231::set_cntl_stat_reg(ds3231_cntl_stat_t data)
{
    uint8_t local_data[] = {0,0,0};
    uint8_t data_length = 0;
    
    local_data[data_length++] = CONTROL;
    local_data[data_length++] = data.control;
    local_data[data_length++] = data.status;

    //users responsibility to make sure data is logical
    return(_p_i2c->write(_w_adrs,(const char*) local_data, data_length));
}


//*********************************************************************
uint16_t Ds3231::get_time(ds3231_time_t* time)
{
    uint16_t rtn_val = 1;
    uint8_t data[3];
    
    data[0] = SECONDS;
    rtn_val = _p_i2c->write(_w_adrs, (const char*) data, 1);
    
    if(!rtn_val)
    {
        rtn_val = _p_i2c->read(_r_adrs,(char *) data, 3);
        
        time->seconds = bcd_2_uchar(data[0]);
        time->minutes = bcd_2_uchar(data[1]);
        time->am_pm = (data[2]&AM_PM);
        time->mode = (data[2]&MODE);
        
        if(time->mode)
        {
            time->hours = bcd_2_uchar((data[2]&0x1F));
        }
        else
        {
            time->hours = bcd_2_uchar((data[2]&0x3F));
        }  
    } 
  
    return(rtn_val);
}


//*********************************************************************
uint16_t Ds3231::get_calendar(ds3231_calendar_t* calendar)
{
    uint16_t rtn_val = 1;
    uint8_t data[4];
    
    data[0] = DAY;
    rtn_val = _p_i2c->write(_w_adrs, (const char*) data, 1);
    
    if(!rtn_val)
    {
        rtn_val = _p_i2c->read(_r_adrs,(char *) data, 4);
        
        calendar->day = bcd_2_uchar(data[0]);
        calendar->date = bcd_2_uchar(data[1]);
        calendar->month = bcd_2_uchar((data[2]&0x1F));
        calendar->year = bcd_2_uchar(data[3]);
    } 
  
    return(rtn_val);
}


//*********************************************************************
uint16_t Ds3231::get_alarm(ds3231_alrm_t* alarm, bool one_r_two)
{
    uint16_t rtn_val = 1;
    uint8_t data[4];
    
    if(one_r_two)
    {
        data[0] = ALRM1_SECONDS;
        rtn_val = _p_i2c->write(_w_adrs, (const char*) data, 1);
        
        if(!rtn_val)
        {
            rtn_val = _p_i2c->read(_r_adrs,(char *) data, 4);
            
            alarm->seconds = bcd_2_uchar(data[0]&0x7F);
            alarm->am1 = (data[0]&ALRM_MASK);
            alarm->minutes = bcd_2_uchar(data[1]&0x7F);
            alarm->am2 = (data[1]&ALRM_MASK);
            alarm->am3 = (data[2]&ALRM_MASK);
            alarm->am_pm = (data[2]&AM_PM);
            alarm->mode = (data[2]&MODE);
            
            if(alarm->mode)
            {
                alarm->hours = bcd_2_uchar((data[2]&0x1F));
            }
            else
            {
                alarm->hours = bcd_2_uchar((data[2]&0x3F));
            }  
            
            if(data[3] & DY_DT)
            {
                alarm->dy_dt = 1;
                alarm->day = bcd_2_uchar(data[3]&0x0F);
            }
            else
            {
                alarm->date = bcd_2_uchar(data[3]&0x3F);
            }
            alarm->am4 = (data[3]&ALRM_MASK);
        } 
    }
    else
    {
        data[0] = ALRM2_MINUTES;
        rtn_val = _p_i2c->write(_w_adrs, (const char*) data, 1);
        
        if(!rtn_val)
        {
            rtn_val = _p_i2c->read(_r_adrs,(char *) data, 4);
            
            alarm->minutes = bcd_2_uchar(data[0]&0x7F);
            alarm->am2 = (data[0]&ALRM_MASK);
            alarm->am3 = (data[1]&ALRM_MASK);
            alarm->am_pm = (data[1]&AM_PM);
            alarm->mode = (data[1]&MODE);
            
            if(alarm->mode)
            {
                alarm->hours = bcd_2_uchar((data[1]&0x1F));
            }
            else
            {
                alarm->hours = bcd_2_uchar((data[1]&0x3F));
            }  
            
            if(data[2] & DY_DT)
            {
                alarm->dy_dt = 1;
                alarm->day = bcd_2_uchar(data[2]&0x0F);
            }
            else
            {
                alarm->date = bcd_2_uchar(data[2]&0x3F);
            }
            alarm->am4 = (data[2]&ALRM_MASK);
        } 
    }
    
    return(rtn_val);
}


//*********************************************************************
uint16_t Ds3231::get_cntl_stat_reg(ds3231_cntl_stat_t* data)
{
    uint16_t rtn_val = 1;
    uint8_t local_data[2];
    
    local_data[0] = CONTROL;
    rtn_val = _p_i2c->write(_w_adrs, (const char*) local_data, 1);
    
    if(!rtn_val)
    {
        rtn_val = _p_i2c->read(_r_adrs,(char *) local_data, 2);
        
        data->control = local_data[0];
        data->status = local_data[1];
    } 
  
    return(rtn_val);
}


//*********************************************************************
uint16_t Ds3231::get_temperature(void)
{
    uint16_t rtn_val = 1;
    uint8_t data[2];
    
    data[0] = MSB_TEMP;
    rtn_val = _p_i2c->write(_w_adrs, (const char*) data, 1);
    
    if(!rtn_val)
    {
        _p_i2c->read(_r_adrs,(char *) data, 2);
        
        rtn_val = data[0] << 8;
        rtn_val |= data[1];
    } 
  
    return(rtn_val);    
}


//*********************************************************************
time_t Ds3231::get_epoch(void)
{
    //system vars
    struct tm sys_time;
    
    //RTC vars
    ds3231_time_t rtc_time = {0,0,0,0,0};
    ds3231_calendar_t rtc_calendar = {0,0,0,0};
    
    get_calendar(&rtc_calendar);
    get_time(&rtc_time);
    
    sys_time.tm_wday = rtc_calendar.day - 1;
    sys_time.tm_mday = rtc_calendar.date;
    sys_time.tm_mon = rtc_calendar.month - 1;
    sys_time.tm_year = rtc_calendar.year + 100;
    
    //check for 12hr or 24hr mode
    if(rtc_time.mode)
    {
        //check am/pm
        if(rtc_time.am_pm  && (rtc_time.hours != 12))
        {
            sys_time.tm_hour = rtc_time.hours + 12;
        }
        else
        {
            sys_time.tm_hour = rtc_time.hours;
        }
        
    }
    else
    {
        //24hr mode
        sys_time.tm_hour = rtc_time.hours;
    }
    
    sys_time.tm_min = rtc_time.minutes;
    sys_time.tm_sec = rtc_time.seconds;
    
    //make epoch time
    return(mktime(&sys_time));
}


//*********************************************************************
uint16_t Ds3231::uchar_2_bcd(uint8_t data)
{
   uint16_t bcd_result = 0;
   
   //Get hundreds
   bcd_result |= ((data/100) << 8);
   data = (data - (data/100)*100);
   
   //Get tens
   bcd_result |= ((data/10) << 4);
   data = (data - (data/10)*10);
   
   //Get ones
   bcd_result |= data;
   
   return(bcd_result);   
}


//*********************************************************************
uint8_t Ds3231::bcd_2_uchar(uint8_t bcd)
{
    uint8_t rtn_val = 0;

    rtn_val += ((bcd&0xf0)>>4)*10;
    rtn_val += (bcd&0x000f);   

    return rtn_val;
}