PIC16F84 Digital Clock / Silent Alarm

This is one of my earliest projects as a maker.

Actually, I've been doing so since I was a little child. And this one is from my early days in Embedded Software.

This is a digital clock project that I've working on since 2006. It's calledSilent Alarm.

It's one of my early projects implementing my favorite Microcontroller Microchip PIC 16F84A.

I wanted to make a silent alarm that awakens the human in gentle and quite way.

I wanted to try the vibration motor used in mobile phones.

Using Seven Segment Displays to display the time and alarm. And controlling vibration motor through a relay controlled by a transistor as a switch.

So here is the circuit to drive it.

Here is my Channel on Youtube:

AeroArduino

Step 1: Components and Circuit

Here is the driver circuit of the vibration motor. This is actually a real time digital clock that can be adjusted to alarm on a specific time of the day.

The circuit is so simple and straight forward.

Here are the required components:

• 1 PIC 16F84A Microcontroller

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, Banggood, Aliexpress , eBay

• 1 7447 BCD to 7 Segment Decoder

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, Banggood, Aliexpress, eBay

• 4 Seven Segment Displays

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, Banggood, Aliexpress, eBay

• 3 5 mm Red LEDs

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, , Banggood, Aliexpress, eBay

• 1 2N2222 Trasistor

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, , Banggood, Aliexpress, eBay

• 1 Relay

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, , Banggood, Aliexpress, eBay

• 3 Push Buttons

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, , Banggood, Aliexpress, eBay

• 3 1K Ohm Resistors

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, Banggood, Aliexpress, eBay

• Virbration Motor

Amazon US, Amazon DE, Amazon FR, Amazon UK, Amazon CA, Amazon ES, Amazon IT,

Souq, Jumia, Banggood, Aliexpress, eBay

Step 2: Software

I must admit it. I've been working with my brother on this project from a long time ago. Documentation is not of high quality that I barely remember how we wrote it.

But I still can remember some concepts. So I'll try to get you to the point.

We've tried to make the assembly software run in exactly equal time-consuming branches in all conditions and on all displays.

We've managed to make all the 7 Segment Displays have the same brightness by making them illuminated by equal time through the program for the best user visual experience and it actually worked.

The Microcontroller worked as the main time keeper. It sends the BCD codes to the BCD Driver IC then it sends codes to the Seven Segment Displays.

The Microcontroller also controls the relay through a transistor to control the vibration motor to vibrate when the alarm rings.

That's all. Thank you for reading.

Here are some of my latest books on Amazon.

Learn By Making

Backyard Wind Turbines