Introduction: DIY Alarm Clock

About: Passionate about electronics and Arduino

After designing the "Clock Set Date Time" and hearing the suggestion of "maewert" I thought it would be a good idea and also useful, add a "wake-up alarm."

A small change to the code and adding a few components: Here's "the Alarm Clock"

Step 1: Material

  • Arduino or Arduino standalone
  • RTC DS1307 or DS3231
  • 20x4 LCD I2C
  • 4 buttons
  • Diodo led
  • 1 Resistor 220 ohm
  • Piezzo Buzzer (from Arduino starter kit)
  • Wires

Step 2: Schematics

Compared to the "Clock Set Date Time" I added a Piezzo buzzer, an LED diode, a resistor of 220 ohm,one button, and as mentioned before, I have listened the suggestion to "maewert" and I removed the resistances to "pull down".

Step 3: Arduino Code

Link libraries:

To remove the "pull down" resistances I had to make a change to the code.

Use the pullup resistors of arduino, and reverse the code logic conditions.








Step 4: The Alarm Code

The activation and deactivation of the alarm clock is controlled by the "P4" button, line 444 "void Alarm()".

To enter the alarm settings, you must use the "P3" "P2" buttons together, line 81 "if((digitalRead(P2)== LOW)&&(digitalRead(P3)== LOW))".

When the alarm is not set, the bottom of the display will show "Alarm Off" when the alarm is active, it shows the time that has been set.

At the scheduled time, the display flashes, the LED lights up, and the buzzer sounds two tones.

To turn off the alarm, you have to act on the P4 button, or, after a minute, it turns off alone

Step 5: Work in Progress

I'm working to put it all in my "Weather Clock"

Microcontroller Contest 2017

Participated in the
Microcontroller Contest 2017