Basics
The Real time clock DS1307 IC basically is stand alone time clock. Well, basically we can use a micrcontroller to keep time, but the value would go off as soon as it is powered off.
The RTC DS1307 is a handy solution to keep time all the way, when it is powered by a coin cell.
It is uses I²C (Inter-Integrated Circuit) protocol, referred to as I-squared-C, I-two-C, or IIC for communication with the micrcontroller.Check the basics of I2C here, if are not familiar with it.
Schematic
Code
- #include <avr\io.h> // io.h contains the defnition of all ports and SFRs
- #include "lcd.h" //User defined LCD library which conatins the lcd routines
- #include "ds1307.h" //User defined library which conatins the RTC(ds1307) routines
- /* start the main program */
- void main()
- {
- unsigned char sec,min,hour,day,month,year;
- /* Initilize the lcd before displaying any thing on the lcd */
- LCD_Init();
- /* Initilize the RTC(ds1307) before reading or writing time/date */
- DS1307_Init();
- /*Set the time and Date only once */
- DS1307_SetTime(0x10,0x40,0x20); // 10:40:20 am
- DS1307_SetDate(0x14,0x11,0x12); // 14th Nov 2012
- /* Display "Time" on first line*/
- LCD_DisplayString("Time: ");
- /* Display "Date" on Second line*/
- LCD_GoToLineTwo();
- LCD_DisplayString("Date: ");
- /* Display the Time and Date continuously */
- while(1)
- {
- /* Read the Time from RTC(ds1307) */
- DS1307_GetTime(&hour,&min,&sec);
- /* Display the time on Firstline-7th position*/
- LCD_GoToXY(0,6);
- LCD_DisplayRtcTime(hour,min,sec);
- /* Read the Date from RTC(ds1307) */
- DS1307_GetDate(&day,&month,&year);
- /* Display the Date on Secondline-7th position*/
- LCD_GoToXY(1,6);
- LCD_DisplayRtcDate(day,month,year);
- }
- }