/*
*****************************************************************************
*
* File Name - rtc_set.c
* Function - Demonstrates writing to the uFlash RTC over the I2C connection
* Note that you should run the rtc_read program to verify the correct time
*
* Once this program is run the RTC on the uFlash will maintain the date & time
* so long as the RTC battery has charge.
*
* You will need:
* (1) uFlash & CCS PIC C compiler (PCM/PCW)
*
* Instructions:
* (1) Modify the data and time to the current values
* (2) Compile & downloading to the uFlash
* (3) Run the rtc_read program to confirm correct opperation
*
*
*	Since there is no logical difference between an I2C chip located on the
*	internal I2C bus of a uFlash and one located on the uConnect bus of a
*	uFlash876B, we can use the uConnect library code to simplify access to
*	the RTC. This means that this code would also work for a uFlash876B with
*	an RTC located externally on the uConnect bus.
*
*****************************************************************************
*/

#include <uF876.h>
#include <uConn.h>
/*
******************************* rtc buffer locations ************************
*/

#define SEC		0			// RTC data offsets in the buffer
#define MIN		1			// note that RTC data is stored in
#define HOUR 	2			// Binary Coded Decimal (BCD) format
#define DOW		3
#define DAY		4
#define MONTH	5
#define YEAR	6

/*
******************************* rtc buffer **********************************
*
*	This RAM buffer mirrors the format of the RTC on chip registers
*	All values are stored in Binary Coded Decimal (BCD)
*	See DS1307 data sheet for details
*
*	Modify these values to represent the current date & time before
*	compiling & running the program.
*
*	Note the use of hex values to represent the the BCD time, so to enter
*	the 23rd of the month enter the value 0x23 in field 4 of the buffer
*/

BYTE rtc[7]=
	{
	0x00,					// Seconds (0-59)  (Bit 7 is the enable flag)
	0x00,					// Minutes (0-59)
	0x00,					// Hours (0-24 or 0-12 am/pm) (Bit 6 12/24 hr ctrl)
	0x03,					// Day of week (1-7)
	0x01,					// Day of month (1-31)
	0x01,					// Month (1-12)
	0x02					// Year (0-99)
	};

/*
***************************** function prototypes ***************************
*/
void set_rtc(void);

/*
*********************************** main ************************************
*
*	Read and display the date & time each time it changes
*/

void main(void)
	{
	set_rtc();					// set the time
	}							// processor to sleep

/*
****************************** set_rtc **************************************
*
*	Copy the contents of the rtc buffer to the rtc chip
*
*	Not used in the rtc_read program
*/
void set_rtc(void)
	{
	uc_wstart(0x68);			// address the rtc (write)
	uc_write(0x00);				// start at location 0 (SEC)
	uc_write(0x80);				// stop the clock to prevent roll over
	uc_write(rtc[MIN]&0x7f);	// write the minutes
	uc_write(rtc[HOUR]&0x3f);	// write the hours
	uc_write(rtc[DOW]&0x07);	// write the day of week
	uc_write(rtc[DAY]&0x3f);	// write the month
	uc_write(rtc[MONTH]&0x1f);	// write the month
	uc_write(rtc[YEAR]);		// write the year
	uc_wstart(0x68);			// start again
	uc_write(0x00);				// start at location 0 (SEC)
	uc_write(rtc[SEC]&0x7f);	// write seconds & enable rtc
	uc_stop();					// end transaction
	}