After I redesigned the power supplies (the system can be powered from 12Vdc) and added a current limiter to the motor supply, the design shifts to digital (more or less). I added a 4-bits counter (74HC193 inherited from the #Discrete YASEP project), and a detector for the timer, based on a plain 74HC04. That's where things got really funky, because I built 1) an oscillator 2) a flip-flop 3) a level corrector, just with this 6×inverters chip.

I try to keep my schematics up to date and I should scan them but I use many transistors, diodes, capacitors and resistors to get things done. I have chosen the "discrete parts" route, because I don't want to write a single line of code. It's both ugly and beautiful, from all the LEDs I have sprinkled all over the board to show the operation of the system...

The schematics need some cleanup before I publish them...