Need Help for RTC trigger Relay

Hello I am really new to programming maybe someone can help me on this topic.
I want to trigger a Relay with an RTC3231 can anybody tell me why this is not working?
Please Help!

Here is the code:

#define RELAY_ON 0
#define RELAY_OFF 1

#define Relay_1 38

#include "Wire.h"
#define DS3231_I2C_ADDRESS 0x68
// Convert normal decimal numbers to binary coded decimal
byte decToBcd(byte val)
{
return( (val/1016) + (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(30,48,0,2,3,8,15);

digitalWrite(Relay_1, RELAY_OFF); // Relay 1
pinMode(Relay_1, OUTPUT); // Relay 1
}
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());
*dayOfMonth = bcdToDec(Wire.read());
*month = 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(" Wochentag: ");
switch(dayOfWeek){
case 1:
Serial.println("Sonntag");
break;
case 2:
Serial.println("Montag");
break;
case 3:
Serial.println("Dienstag");
break;
case 4:
Serial.println("Mittwoch");
break;
case 5:
Serial.println("Donnerstag");
break;
case 6:
Serial.println("Freitag");
break;
case 7:
Serial.println("Samstag");
break;
}
}
void loop()
{
displayTime(); // display the real-time clock data on the Serial Monitor,
delay(1000); // every second
}
void Relais1() {

if ( hour()== 16)
{
digitalWrite(Relay_1, RELAY_ON);
}

}

RTC_with_day_of_week.ino (3.17 KB)

problem already solved :slight_smile: