Recently I was asked for gerber files for one of my old projects - "Simple Timer with PIC16F628A", but unfortunately the files of that project were lost. I decided to make a new project with more modern and smaller microcontroller - PIC16F18313, which have 8 pin only. To make that possible the display has to be with 2 wire serial communication. I already had such a display - a 4 digit 7 segment module with TM1637, and I already learned how to use it.
Here is the schematic:
Here the archive with all project files: Timer_PIC16F18313
I only test the schematic on a breadboard, so there is always a possibility for errors in the PCB. Check everything for yourself and use the files on your own responsibility.