This is basically the arduino.cc sample turned into a library for easier reusability. It's not perfect but it does the job. void clockWrite(byte year, byte month, byte day, byte wday, byte hours, byte ...

Alarm Clock with DS1302 RTC This code is designed to work with various components, including the DS1302 RTC module, a 4x4 keypad, an LCD with I2C interface, an Arduino board, and a buzzer.