Get ALL the components you need. It might sound simple, but I went through lots of trouble to get it.
Install Eagle CAD (free version)
Clone repository https://github.com/atheros/backtothefuture-clock
You'll find sourcecode, schematics and board designs there.
Create (etch and solder) 5 PCB from big-module-shift and big-module-test - those are the display PCBs and drivers for 14-segment displays.
Create 2 boards of each of the following:
Create (etch and solder) one PCB of each of the following:
- main, a.k.a Time Circuit Clock PCB
Solder display PCBs to display driver PCBs using angular pin headers and in case of 14-segments, an additional ribbon cable connection is required.
Connect driver boards with ribbon cables. 7-segment display boards and led board uses 10 wire cable, 14-segment displays use 12 wire cables.
Note that there is no 12 wire IDC plug, so I used 14 wire plug and left the last two wires unconnected on the board.
You can see the connection here:
Red wires are for 14-segment displays, blue for 7-segment displays.
Load the sketches:
- DisplayController to display-controller board
- MainController to main board
Make sure you remove the LED from pin 13 from the Arduino on the Time Circuit Main board or your keypad won't work correctly.