/*****************************************************************************
 *
 * Real Time Clock Calender
 *
 *****************************************************************************
 * FileName:        rtcc.c
 * Dependencies:
 * Processor:       PIC24
 * Compiler:        C30 xx.xx or higher
 * Linker:          MPLINK 03.20.01 or higher
 * Company:         Microchip Technology Incorporated
 *
 * Software License Agreement
 *
 * The software supplied herewith by Microchip Technology Incorporated
 * (the "Company") is intended and supplied to you, the Company's
 * customer, for use solely and exclusively with products manufactured
 * by the Company.
 *
 * The software is owned by the Company and/or its supplier, and is
 * protected under applicable copyright laws. All rights are reserved.
 * Any use in violation of the foregoing restrictions may subject the
 * user to criminal sanctions under applicable laws, as well as to
 * civil liability for the breach of the terms and conditions of this
 * license.
 *
 * THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION. NO WARRANTIES,
 * WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
 * TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
 * IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
 *
 *
 * Author               Date        Comment
 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * Chris Valenti        05-26-05    ...
 * Ross Fosler          06-06-2005  Several changes
 * Anton Alkhimenok     10-21-2005  Get/Set functions
 * KO                   12-Feb-2008 Added default time/date specification
 *                                  Removed "m" macro designations
 *                                  Null terminated strings
 *****************************************************************************/
#include "GenericTypedefs.h"
#include "HardwareProfile.h"
#include "rtcc.h"

/*****************************************************************************
 * Structures: _time and _time_chk
 *
 * Overview: These structures contain the time and date.
 * RTCCProcessEvents updates them. _time_chk is used as input/output for
 * get/set operations.
 *
 *****************************************************************************/
RTCC _time;
RTCC _time_chk;
/*****************************************************************************
 * Arrays: _time_str and _date_str
 *
 * Overview: These arrays contain the time and date strings.
 * RTCCProcessEvents updates them.
 *
 *****************************************************************************/
char _time_str[16] = "                ";        // Sat 10:01:15
char _date_str[16] = "                ";        // Sep 30, 2005

// The flag stops updating time and date and used for get/set operations.
unsigned char _rtcc_flag;
/*****************************************************************************
 * Function: RTCCProcessEvents
 *
 * Preconditions: RTCCInit must be called before.
 *
 * Overview: The function grabs the current time from the RTCC and translate
 * it into strings.
 *
 * Input: None.
 *
 * Output: It update time and date strings  _time_str, _date_str,
 * and _time, _time_chk structures.
 *
 *****************************************************************************/
void RTCCProcessEvents(void)
{
    // Process time object only if time is not being set
    while (!_rtcc_flag) {
        // Grab the time
        RCFGCALbits.RTCPTR = 0;
        _time.prt00 = RTCVAL;
        RCFGCALbits.RTCPTR = 1;
        _time.prt01 = RTCVAL;
        RCFGCALbits.RTCPTR = 2;
        _time.prt10 = RTCVAL;
        RCFGCALbits.RTCPTR = 3;
        _time.prt11 = RTCVAL;

        // Grab the time again
        RCFGCALbits.RTCPTR = 0;
        _time_chk.prt00 = RTCVAL;
        RCFGCALbits.RTCPTR = 1;
        _time_chk.prt01 = RTCVAL;
        RCFGCALbits.RTCPTR = 2;
        _time_chk.prt10 = RTCVAL;
        RCFGCALbits.RTCPTR = 3;
        _time_chk.prt11 = RTCVAL;

        // Verify there is no roll-over
        if ((_time.prt00 == _time_chk.prt00) &&
            (_time.prt01 == _time_chk.prt01) &&
            (_time.prt10 == _time_chk.prt10) &&
            (_time.prt11 == _time_chk.prt11))
        {
            switch (_time.mth) {
                default:
                case 0x01: _date_str[0] = 'J'; _date_str[1] = 'a'; _date_str[2] = 'n'; break;
                case 0x02: _date_str[0] = 'F'; _date_str[1] = 'e'; _date_str[2] = 'b'; break;
                case 0x03: _date_str[0] = 'M'; _date_str[1] = 'a'; _date_str[2] = 'r'; break;
                case 0x04: _date_str[0] = 'A'; _date_str[1] = 'p'; _date_str[2] = 'r'; break;
                case 0x05: _date_str[0] = 'M'; _date_str[1] = 'a'; _date_str[2] = 'y'; break;
                case 0x06: _date_str[0] = 'J'; _date_str[1] = 'u'; _date_str[2] = 'n'; break;
                case 0x07: _date_str[0] = 'J'; _date_str[1] = 'u'; _date_str[2] = 'l'; break;
                case 0x08: _date_str[0] = 'A'; _date_str[1] = 'u'; _date_str[2] = 'g'; break;
                case 0x09: _date_str[0] = 'S'; _date_str[1] = 'e'; _date_str[2] = 'p'; break;
                case 0x10: _date_str[0] = 'O'; _date_str[1] = 'c'; _date_str[2] = 't'; break;
                case 0x11: _date_str[0] = 'N'; _date_str[1] = 'o'; _date_str[2] = 'v'; break;
                case 0x12: _date_str[0] = 'D'; _date_str[1] = 'e'; _date_str[2] = 'c'; break;
            }

            _date_str[3] = ' ';
            _date_str[6] = ',';
            _date_str[7] = ' ';
            _date_str[8] = '2';
            _date_str[9] = '0';

            _date_str[4] = (_time.day >> 4) + '0';
            _date_str[5] = (_time.day & 0xF) + '0';

            _date_str[10] = (_time.yr >> 4) + '0';
            _date_str[11] = (_time.yr & 0xF) + '0';

            _date_str[12] = 0;

            switch (_time.wkd) {
                default:
                case 0x00: _time_str[0] = 'S'; _time_str[1] = 'u'; _time_str[2] = 'n'; break;
                case 0x01: _time_str[0] = 'M'; _time_str[1] = 'o'; _time_str[2] = 'n'; break;
                case 0x02: _time_str[0] = 'T'; _time_str[1] = 'u'; _time_str[2] = 'e'; break;
                case 0x03: _time_str[0] = 'W'; _time_str[1] = 'e'; _time_str[2] = 'd'; break;
                case 0x04: _time_str[0] = 'T'; _time_str[1] = 'h'; _time_str[2] = 'u'; break;
                case 0x05: _time_str[0] = 'F'; _time_str[1] = 'r'; _time_str[2] = 'i'; break;
                case 0x06: _time_str[0] = 'S'; _time_str[1] = 'a'; _time_str[2] = 't'; break;
            }

            _time_str[3] = ' ';
            _time_str[6] = ':';
            _time_str[9] = ':';

            _time_str[4] = (_time.hr >> 4) + '0';
            _time_str[5] = (_time.hr & 0xF) + '0';

            _time_str[7] = (_time.min >> 4) + '0';
            _time_str[8] = (_time.min & 0xF) + '0';

            _time_str[10] = (_time.sec >> 4) + '0';
            _time_str[11] = (_time.sec & 0xF) + '0';

            _time_str[12] = 0;

            break;
        }
    }
}

/*****************************************************************************
 * Function: RTCCInit
 *
 * Preconditions: RTCCInit must be called before.
 *
 * Overview: Enable the oscillator for the RTCC
 *
 * Input: None.
 *
 * Output: None.
 *****************************************************************************/
void RTCCInit(void)
{
    // Enables the LP OSC for RTCC operation
    asm("mov #OSCCON,W1");
    asm("mov.b  #0x02, W0");
    asm("mov.b  #0x46, W2");
    asm("mov.b  #0x57, W3");
    asm("mov.b  W2, [W1]");
    asm("mov.b  W3, [W1]");
    asm("mov.b  W0, [W1]");

    // Set the RTCC to a default value, and start it.
    RCFGCAL = 0x0000;
    RTCCUnlock();
    RCFGCALbits.RTCEN = 1;
    RTCCOn();
    RTCCSetBinSec(    RTCC_DEFAULT_SECOND );
    RTCCSetBinMin(    RTCC_DEFAULT_MINUTE );
    RTCCSetBinHour(   RTCC_DEFAULT_HOUR );
    RTCCSetBinWkDay(  RTCC_DEFAULT_WEEKDAY );
    RTCCSetBinDay(    RTCC_DEFAULT_DAY );
    RTCCSetBinMonth(  RTCC_DEFAULT_MONTH );
    RTCCSetBinYear(   RTCC_DEFAULT_YEAR );
    RTCCSet();

}

/*****************************************************************************
 * Function: RTCCSet
 *
 * Preconditions: None.
 *
 * Overview: The function upload time and date from _time_chk into clock.
 *
 * Input: _time_chk - structure containing time and date.
 *
 * Output: None.
 *
 *****************************************************************************/
void RTCCSet(void)
{
    RTCCUnlock();           // Unlock the RTCC
    // Set the time
    RCFGCALbits.RTCPTR = 0;
    RTCVAL = _time_chk.prt00;
    RCFGCALbits.RTCPTR = 1;
    RTCVAL = _time_chk.prt01;
    RCFGCALbits.RTCPTR = 2;
    RTCVAL = _time_chk.prt10;
    RCFGCALbits.RTCPTR = 3;
    RTCVAL = _time_chk.prt11;
    RTCCLock();         // Lock the RTCC
    _rtcc_flag = 0;         // Release the lock on the time
}

/*****************************************************************************
 * Function: RTCCUnlock
 *
 * Preconditions: None.
 *
 * Overview: The function allows a writing into the clock registers.
 *
 * Input: None.
 *
 * Output: None.
 *
 *****************************************************************************/
void RTCCUnlock(void)
{
    asm volatile("disi  #5");
    asm volatile("mov   #0x55, w7");
    asm volatile("mov   w7, _NVMKEY");
    asm volatile("mov   #0xAA, w8");
    asm volatile("mov   w8, _NVMKEY");
    asm volatile("bset  _RCFGCAL, #13");
    asm volatile("nop");
    asm volatile("nop");
}

/*****************************************************************************
 * Function: RTCCSetBinSec
 *
 * Preconditions: None.
 *
 * Overview: The function verifies setting seconds range, translates it into
 * BCD format and writes into _time_chk structure. To write the structure into
 * clock RTCCSet must be called.
 *
 * Input: Seconds binary value.
 *
 * Output: Checked BCD value in _time_chk structure.
 *
 *****************************************************************************/
void RTCCSetBinSec(unsigned char Sec)
{
    if(Sec == 0xff) Sec = 59;
    if(Sec == 60)   Sec = 0;
    RTCCSetSec(RTCCBin2Dec(Sec));
}

/*****************************************************************************
 * Function: RTCCSetBinMin
 *
 * Preconditions: None.
 *
 * Overview: The function verifies a setting minutes range, translates it into
 * BCD format and writes into _time_chk structure. To write the structure into
 * clock RTCCSet must be called.
 *
 * Input: Minutes binary value.
 *
 * Output: Checked BCD value in _time_chk structure.
 *
 *****************************************************************************/
void RTCCSetBinMin(unsigned char Min)
{
    if(Min == 0xff) Min = 59;
    if(Min == 60)   Min = 0;
    RTCCSetMin(RTCCBin2Dec(Min));
}

/*****************************************************************************
 * Function: RTCCSetBinHour
 *
 * Preconditions: None.
 *
 * Overview: The function verifies a setting hours range, translates it into
 * BCD format and writes into _time_chk structure. To write the structure into
 * clock RTCCSet must be called.
 *
 * Input: Hours binary value.
 *
 * Output: Checked BCD value in _time_chk structure.
 *
 *****************************************************************************/
void RTCCSetBinHour(unsigned char Hour)
{
    if(Hour == 0xff) Hour = 23;
    if(Hour == 24)   Hour = 0;
    RTCCSetHour(RTCCBin2Dec(Hour));
}

/*****************************************************************************
 * Function: RTCCCalculateWeekDay
 *
 * Preconditions: Valid values of day, month and year must be presented in
 * _time_chk structure.
 *
 * Overview: The function reads day, month and year from _time_chk and
 * calculates week day. Than It writes result into _time_chk. To write
 * the structure into clock RTCCSet must be called.
 *
 * Input: _time_chk with valid values of day, month and year.
 *
 * Output: Zero based week day in _time_chk structure.
 *
 *****************************************************************************/
void RTCCCalculateWeekDay()
{
    const char MonthOffset[] =
                    //jan feb mar apr may jun jul aug sep oct nov dec
                    {   0,  3,  3,  6,  1,  4,  6,  2,  5,  0,  3,  5 };
    unsigned Year;
    unsigned Month;
    unsigned Day;
    unsigned Offset;

    // calculate week day
    Year  = RTCCGetBinYear();
    Month = RTCCGetBinMonth();
    Day  = RTCCGetBinDay();

    // 2000s century offset = 6 +
    // every year 365%7 = 1 day shift +
    // every leap year adds 1 day
    Offset = 6 + Year + Year/4;
    // Add month offset from table
    Offset += MonthOffset[Month-1];
    // Add day
    Offset += Day;

    // If it's a leap year and before March there's no additional day yet
    if((Year%4) == 0)
        if(Month < 3)
            Offset -= 1;

    // Week day is
    Offset %= 7;

    RTCCSetWkDay(Offset);
}

/*****************************************************************************
 * Function: RTCCSetBinDay
 *
 * Preconditions: None.
 *
 * Overview: The function verifies a setting day range, translates it into
 * BCD format and writes into _time_chk structure. To write the structure into
 * clock RTCCSet must be called.
 *
 * Input: Day binary value.
 *
 * Output: Checked BCD value in _time_chk structure.
 *
 *****************************************************************************/
void RTCCSetBinDay(unsigned char Day)
{
    const char MonthDaymax[] =
                    //jan feb mar apr may jun jul aug sep oct nov dec
                    {  31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    unsigned Daymax;
    unsigned Month;
    unsigned Year;

    Month = RTCCGetBinMonth();
    Year = RTCCGetBinYear();

    Daymax = MonthDaymax[Month-1];

    // February has one day more for a leap year
    if(Month == 2)
    if( (Year%4) == 0)
        Daymax++;

    if(Day == 0) Day = Daymax;
    if(Day > Daymax) Day = 1;
    RTCCSetDay(RTCCBin2Dec(Day));
}

/*****************************************************************************
 * Function: RTCCSetBinMonth
 *
 * Preconditions: None.
 *
 * Overview: The function verifies a setting month range, translates it into
 * BCD format and writes into _time_chk structure. To write the structure into
 * clock RTCCSet must be called.
 *
 * Input: Month binary value.
 *
 * Output: Checked BCD value in _time_chk structure.
 *
 *****************************************************************************/
void RTCCSetBinMonth(unsigned char Month)
{
    if(Month < 1)  Month = 12;
    if(Month > 12) Month = 1;
    RTCCSetMonth(RTCCBin2Dec(Month));
}

/*****************************************************************************
 * Function: RTCCSetBinYear
 *
 * Preconditions: None.
 *
 * Overview: The function verifies a setting year range, translates it into
 * BCD format and writes into _time_chk structure. To write the structure into
 * clock RTCCSet must be called.
 *
 * Input: Year binary value.
 *
 * Output: Checked BCD value in _time_chk structure.
 *
 *****************************************************************************/
void RTCCSetBinYear(unsigned char Year)
{
    if(Year == 0xff) Year = 99;
    if(Year == 100)  Year = 0;
    RTCCSetYear(RTCCBin2Dec(Year));

    // Recheck day. Leap year influences to Feb 28/29.
    RTCCSetBinDay(RTCCGetBinDay());
}

/*****************************************************************************
 * EOF
 *****************************************************************************/
