Retro 7 segment digital clock

Description

A friend of mine presented me with a mechanical digital clock from the 70's. The display mechanism had broke and attempts to fix it failed. It was decided that it would be easier to remove the mechanism and use a 7 segment display. Fortunately, there were 7 segment digits available that fitted perfectly in the clock's display the window!

This project features an RTC which accurately keeps time even if the clock is ever switched off ! There 2 buttons for navigating menu and changing clock values, and the current temperature can be displayed by pressing the second button when the clock is running. The clock automatically adjusts for BST by automatically adding or subtracting an hour early in the morning. The device is powered by 5v on USB..

Details

Features

Multiplexed 7 segment display
Accurate time keeping with RTC and battery backup (keeps time when powered off)
Menu and change value/show temperature buttons
Temperature displayed to 1 decimal point
Automatic adjustment for British Summer Time (BST)
Powered via 5v USB
Scrolling messages

Building

The circuit is simple to build but connecting all the 7 segment LEDs get tricky.
Follow the attached schematics or breadboard view
I CNCed a circuit board so that the 7 segment digits would fit the window in the clock exactly. These files are attached.

Coding

The source code is attached. I used Sublime Text for editing and Arduino IDE 1.6.5 for uploading

Files

LittleClock.ino

The main program

ino - 15.61 kB - 06/05/2018 at 20:07

Download

Display Schematic.png

Display board schematic for 7 segment display @ 600 DPI

Portable Network Graphics (PNG) - 52.42 kB - 05/30/2018 at 10:23

Preview

Download

Display Board.png

Display board for 7 segment display @ 600 DPI

Portable Network Graphics (PNG) - 77.51 kB - 05/30/2018 at 10:22

Preview

Download

Schematic.png

Circuit schematic

Portable Network Graphics (PNG) - 178.54 kB - 05/30/2018 at 09:52

Preview

Download

Breadboard.png

Circuit on a breadboard

Portable Network Graphics (PNG) - 461.53 kB - 05/30/2018 at 09:51

Preview

Download

Components

4 × 7 segement digit display common cathode

1 × Arduino Pro Mini 5v

1 × DS3231 RTC

2 × Push button

8 × 150 Ohm resistors 1/4W

Discussions

mitch wrote 08/20/2020 at 07:34

mitch@scotchandsofa.co.za hi . love this clock. can you pls help. keep getting 'PULLUP' was not decared in scope

Are you sure? yes | no

Supercrab wrote 08/22/2020 at 12:52

Thank you! I'm not sure what would cause that error. What arduino do you have? What version IDE are you running? Have you installed the button library?
Try using INPUT_PULLUP

Are you sure? yes | no

Retro 7 segment digital clock

Description

Details

Files

LittleClock.ino

Display Schematic.png

Display Board.png

Schematic.png

Breadboard.png

Components

Discussions

Similar Projects

Voltmeter Clock

Exasperating Clock

Roman LED Clock

Retro 7 segment digital clock

Become a Hackaday.io member

Just one more thing

Description

Details

Files

Components

Enjoy this project?

Discussions

Become a Hackaday.io Member

Similar Projects

Does this project spark your interest?

Report project as inappropriate

Send message

Remove Member