Arduino Based 7 Segment Display Clock

I will show you how to make your own Arduino based 7 segment display (4 digits) clock with sound activation feature!!

The circuit uses the ATmega328p micro controller (the same as the Arduino UNO board) and the DS1302 clock IC. You can easily set/change the time by pressing the setup buttons. The clock can be activated by pressing an button or by making a sound (e.g. clap, blowing, whistle) near the microphone. It can be powered on with two AA batteries (3V) or with an USB cable from your computer (or cellphone's charger, max 5V).

Step 1: What You Need?

1 x Arduino UNO 

1 x USB Type-B Cable

4 x 7 Segment LED
1 x 16MHz Crystal Oscillator 
2 x 22pF Capacitor 
1 x 100nF Capacitor 
1 x 10k Ohm Resistor 
1 x 120 Ohm Resistor 
2 x LEDs (Red)
3 x Pushbuttons 
1 x DS1302 Clock Module 
1 x Prototyping PCB Circuit Board Stripboard

1 x Computer with Arduino IDE installed
Male-to-Male Jumper Wires 
Female-to-Male Jumper Wires

Optional
2 x 1.5V AA Battery & 1 x 4xAA Battery Holder
1 x 9V Battery & 9V Battery Holder
1 x Mini Breadboard or Breadboard
4 Digits Segment LED

Cable Cover
Arduino Compatible UNO Ultimate Starter Kit / Learning Kit
USB To Power Jack Cable

Don't have components? Don't worry. Just click the component's name. 

Step 2: Build Your Circuit.

The connections are easy, see the image above with the breadboard circuit schematic.

Buttons:

• Select/Set function button to Arduino pin A0
• Change time/min function button to Arduino pin A1
• Show time button to Arduino pin A2

Microphone:

• Mic goes to Arduino pin A3

DS1302:

• CE pin to Arduino pin 0
• I/O pin to Arduino pin 1
• SCLK pin to Arduino pin 2

LEDs:

• Two Red LEDs to Arduino pin A4

7 segment displays:

Connect the same letters of 7 seg digits pins with others

• 1 - "E" - Arduino pin 6
• 2 - "D" - Arduino pin 7
• 4 - "C" - Arduino pin 8
• 6 - "B" - Arduino pin 12
• 7 - "A" - Arduino pin 11
• 9 - "F" - Arduino pin 10
• 10 - "G" - Arduino pin 9

Common cathode pins:

• 1st digit CC pins to Arduino pin 3
• 2st digit CC pins to Arduino pin 4
• 3rd digit CC pins to Arduino pin 5
• 4th digit CC pins to Arduino pin 13

------------------------------------------

Tip: Make your circuit on breadboard first 

Step 3: Upload The Code To Board.

If you have any problems with sound activation feature change the values 660 and 750 (line 127):

if ((digitalRead(showBT) == LOW) || (sound<660 || sound>750))

Step 4: Make The Box.

I used plexiglass pieces to build my clock box.

Step 5: Done!!

You have successfully completed this guide and now you have your own Arduino clock with sound activation feature in your desk!

Source:http://www.instructables.com/id/Arduino-7-Segment-Displau-Clock-sound-Activation/?ALLSTEPS

7 segment display Arduino UNO R3 button clock DS1302 easy LED mic project

Arduino Based Countdown Timer With Setup Buttons

I will show you how to make your own Arduino two digit countdown timer. We will be able to set the timer by pressing the setup buttons. We will use two digits seven segment display, so the maximum countdown time will be 99 seconds. 

Watch the video below:

Step 1: What You Need?

1 x Arduino UNO R3
1 x Mini Breadboard
2 x 7 Segment Displays (You can use common cathode or common anode type)
3 x Buttons
1 x USB Arduino Cable
Wires 
1 x Computer with Arduino Software installed

Don't have components? Don't worry. Just click the component's name. 

Step 2: Built Your Circuit. 

- The segments A-G: 

     A, B, C, D, E, F, G >> 10, 9, 8, 7, 6, 11, 12

- CC* or CA* pins of 7 Segment Displays >> Arduino pin 4 & 5  

- Start/Stop button >> pin 2

- Change button >> pin 3 

- Set button >> pin 13

- Dot pin of RIGHT digit >> pin A0

- Dot pin of LEFT digit >> pin A1

*CC- Common Cathode

*CA- Common Anode

(NOTE: You can connect one 220 Ohm resistor to each pin - except "CC" or "CA" if you want.)

Step 3: Upload Code To Board. 

(NOTE: If you have Common Anode 7 Segment Display type just delete the line 24 "disp.setCommonCathode(),")

Download: 

Arduino software


Sources:[http://www.instructables.com/id/Arduino-Countdown-Timer-With-Setup-Buttons/]

7 segment display Arduino Arduino UNO R3 Basic button countdown easy project simple Timer