• 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


  • 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.


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