Dear all,
i just copied this code from Arduino website. I wanna understand this code. How they specified i2c address has 0x68. How they taken in to consideration. Code is working fine.
how they assigned 0x68 and why they put byte Zero=0x00;
#define DS1307_ADDRESS 0x68
byte zero = 0x00; //workaround for issue #527
main code:
#include"Wire.h"
#define DS1307_ADDRESS 0x68
byte zero = 0x00; //workaround for issue #527
void setup(){
Wire.begin();
Serial.begin(9600);
setDateTime(); //MUST CONFIGURE IN FUNCTION
}
void loop(){
printDate();
delay(1000);
}
void setDateTime(){
byte second = 45; //0-59
byte minute = 06; //0-59
byte hour = 11; //0-23
byte weekDay = 2; //1-7
byte monthDay = 27; //1-31
byte month = 2; //1-12
byte year = 13; //0-99
Wire.beginTransmission(DS1307_ADDRESS);
Wire.write(zero); //stop Oscillator
Wire.write(decToBcd(second));
Wire.write(decToBcd(minute));
Wire.write(decToBcd(hour));
Wire.write(decToBcd(weekDay));
Wire.write(decToBcd(monthDay));
Wire.write(decToBcd(month));
Wire.write(decToBcd(year));
Wire.write(zero); //start
Wire.endTransmission();
}
byte decToBcd(byte val){
// Convert normal decimal numbers to binary coded decimal
return ( (val/10*16) + (val%10) );
}
byte bcdToDec(byte val) {
// Convert binary coded decimal to normal decimal numbers
return ( (val/16*10) + (val%16) );
}
void printDate(){
// Reset the register pointer
Wire.beginTransmission(DS1307_ADDRESS);
Wire.write(zero);
Wire.endTransmission();
Wire.requestFrom(DS1307_ADDRESS, 7);
int second = bcdToDec(Wire.read());
int minute = bcdToDec(Wire.read());
int hour = bcdToDec(Wire.read() & 0b111111); //24 hour time
int weekDay = bcdToDec(Wire.read()); //0-6 -> sunday - Saturday
int monthDay = bcdToDec(Wire.read());
int month = bcdToDec(Wire.read());
int year = bcdToDec(Wire.read());
/* int second = 11;
int minute =18;
int hour = 18;
int weekDay = 1;
int monthDay = 2;
int month = 11;
int year = 12;
*/
//print the date EG 3/1/11 23:59:59
Serial.print(monthDay);
Serial.print("/");
Serial.print(month);
Serial.print("/");
Serial.print(year);
Serial.print(" ");
Serial.print(hour);
Serial.print(":");
Serial.print(minute);
Serial.print(":");
Serial.println(second);
}