Four Digit Seven Segments Display Counter/thermometer

Introduction: Four Digit Seven Segments Display Counter/thermometer

Hi there! Today I'm gonna show you my last project I've made. Firstly, when I've started the project was about a counter with a 4 digit 7 segments multiplexed display, for digital electronic class at University.

For this project I've used those parts:
1. 4 digit 7 segment display common anode
2. Atmega8 microcontroller
3. 7805 voltage regulator
4. 16MHz quartz
5. 2 x 22pF
6. 1N4001 diode
7. 100uF electrolytic cap
8. 100nF ceramic cap
9. female headers
10. DC barrel power jack connector
11. prototyping board
12. some wires from a HDD ribbon cable.
13. LM335 themperature sensor + 2 x 1K resistors

The tools used in this project are:

- Soldering iron
- Solder pump
- Soldering wire
- Hemostats
- Wire strippers
- Third hand
- Poxipol to glue the barrel jack connector to the board

As inspiration I've used THIS PROJECT and THIS PROJECT.

The schematic is made by myself in Fritzing using the descriptions from that project. So, like you have already seen I didn't actually bothered to change the order of the pins in the code to avoid that crazy wiring. The code is made so you don't need any resistor for the display because each anode is controlled using PWM.
First tests were made using Arduino UNO R2 and then after the code was ok, I've started the building. There are also 3 photos with some details when the board was almost 90% finished, I think. The last photo is with LM335 temperature sensor added to the counter. The sensor is connected to A2 pin of Atmega8.

Link of the counter code: here
Link of the thermometer code: here

Note that thermometer code require the sevseg library for Arduino. You can find the library RIGHT HERE!
This is it! I hope you enjoyed and don't forget to press FOLLOW+ button! :) Cheers!
P.S.: Sorry for my spelling mistakes!

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    1 year ago

    This is an rather old tread.
    Nobody noticed it does not work using the ATMega8?
    It requieres using the ATMega328P, be cause only this chip has the four mentioned PWM pins.
    NOTA:digitii trebuie conectati la pini PWM!!!

    My translation and notes:
    // NOTE: The digits must be connected to PWM pins !!!
    // ATMega8 PB1,PB2,PB3 = Pin15,16,17 am Chip
    // ATMega328 PB1,PB2,PB3 und PD5,PD6 = Pin 15,16,17, 11,12 am Chip


    8 years ago on Introduction

    Hi, nice work, can you post tour thermomether code again, can't find it, thx

    Timofte Andrei
    Timofte Andrei

    Reply 8 years ago on Introduction

    oh...sorry for that! i will fix that as soon as i can! have a good time!


    9 years ago on Introduction

    great job! simple and useful to add to the design of other electronics to monitor temp!

    Timofte Andrei
    Timofte Andrei

    Reply 9 years ago on Introduction

    thanks for your reply :) this display can be used to show multiple information such as voltage, amperage, wattage, and so on. feel free to modify as you like :) thanks again for your comment! cheers!