Arduino Alarm Scheduler Known as Larmie

Overview

The project aims to build an alarm clock that can be scheduled automatically using the functionalities of an Arduino to avoid pressing the alarm clock button over and over again.

Explanation

There are four different components that comprise the Larmie project which includes a calendar system that is downloadable, a computer for updating the Arduino on the alarm set time, a custom shield Arduino, a simple alarm clock with optional interface cable. The LM8560 type of alarm clock is preferred since it has an all-in-one feature.

To simulate pressing the buttons on the clock, the voltage on the LM8560 input pins should be twiddled. A 7405 hex inverter with open collectors was used where the hex refers to 6 inverters on the chip. The gate output will be pulled to 0V when it is a logical false but the pin floats when it is logical true. The voltage can be pulled to the clock’s high with a resistor with an indicator using an LED.

A serial connection is used to inform the Arduino about the alarm. Avoiding setting off the alarm while setting it is the biggest challenge in writing the Larmie firmware.