Sorry, should have said line 19 only leave line 18 as is, try this, I will set time & date to UTC.
#include "Wire.h"
#define DS3231_I2C_ADDRESS 0x68
// Convert normal decimal numbers to binary coded decimal
byte decToBcd(byte val)
{
return( (val/10*16) + (val%10) );
}
// Convert binary coded decimal to normal decimal numbers
byte bcdToDec(byte val)
{
return( (val/16*10) + (val%16) );
}
void setup()
{
Wire.begin();
Serial.begin(9600);
//set the initial time here:
//DS3231 seconds, minutes, hours, day, date, month, year
setDS3231time(0,40,6,2,18,6,18); // <<< set time & date here
}
void setDS3231time(byte second, byte minute, byte hour, byte dayOfWeek, byte
dayOfMonth, byte month, byte year)
{
// sets time and date data to DS3231
Wire.beginTransmission(DS3231_I2C_ADDRESS);
Wire.write(0); // set next input to start at the seconds register
Wire.write(decToBcd(second)); // set seconds
Wire.write(decToBcd(minute)); // set minutes
Wire.write(decToBcd(hour)); // set hours
Wire.write(decToBcd(dayOfWeek)); // set day of week (1=Sunday, 7=Saturday)
Wire.write(decToBcd(dayOfMonth)); // set date (1 to 31)
Wire.write(decToBcd(month)); // set month
Wire.write(decToBcd(year)); // set year (0 to 99)
Wire.endTransmission();
}
void readDS3231time(byte *second,
byte *minute,
byte *hour,
byte *dayOfWeek,
byte *dayOfMonth,
byte *month,
byte *year)
{
Wire.beginTransmission(DS3231_I2C_ADDRESS);
Wire.write(0); // set DS3231 register pointer to 00h
Wire.endTransmission();
Wire.requestFrom(DS3231_I2C_ADDRESS, 7);
// request seven bytes of data from DS3231 starting from register 00h
*second = bcdToDec(Wire.read() & 0x7f);
*minute = bcdToDec(Wire.read());
*hour = bcdToDec(Wire.read() & 0x3f);
*dayOfWeek = bcdToDec(Wire.read());
*month = bcdToDec(Wire.read());
*dayOfMonth = bcdToDec(Wire.read());
*year = bcdToDec(Wire.read());
}
void displayTime()
{
byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
// retrieve data from DS3231
readDS3231time(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month,
&year);
// send it to the serial monitor
Serial.print(hour, DEC);
// convert the byte variable to a decimal number when displayed
Serial.print(":");
if (minute<10)
{
Serial.print("0");
}
Serial.print(minute, DEC);
Serial.print(":");
if (second<10)
{
Serial.print("0");
}
Serial.print(second, DEC);
Serial.print(" ");
Serial.print(dayOfMonth, DEC);
Serial.print("/");
Serial.print(month, DEC);
Serial.print("/");
Serial.print(year, DEC);
Serial.print(" Day of week: ");
switch(dayOfWeek){
case 1:
Serial.println("Sunday");
break;
case 2:
Serial.println("Monday");
break;
case 3:
Serial.println("Tuesday");
break;
case 4:
Serial.println("Wednesday");
break;
case 5:
Serial.println("Thursday");
break;
case 6:
Serial.println("Friday");
break;
case 7:
Serial.println("Saturday");
break;
}
Serial.println();
}
void loop()
{
displayTime(); // display the real-time clock data on the Serial Monitor,
delay(1000); // every second
}
Here's a few lines from serial monitor:
6:42:00 6/18/18 Day of week: Monday
6:42:01 6/18/18 Day of week: Monday
6:42:02 6/18/18 Day of week: Monday
6:42:03 6/18/18 Day of week: Monday
6:42:04 6/18/18 Day of week: Monday
6:42:05 6/18/18 Day of week: Monday
6:42:06 6/18/18 Day of week: Monday
6:42:07 6/18/18 Day of week: Monday
6:42:08 6/18/18 Day of week: Monday
6:42:09 6/18/18 Day of week: Monday
6:42:10 6/18/18 Day of week: Monday
6:42:11 6/18/18 Day of week: Monday
6:42:12 6/18/18 Day of week: Monday
6:42:13 6/18/18 Day of week: Monday
6:42:14 6/18/18 Day of week: Monday
