Do you need to supply higher voltage to a solenoid if using a flyback diode

I must say that using a "bare" ATmega328 really is "doing it the hard way", making things more difficult and potentially introducing many minor problems. :face_with_raised_eyebrow:

If you use a Pro Mini (clone) it is cheaper, you have properly configured bypass capacitors, crystal or resonator clock, reset circuitry and a convenient indicator in a reliable form.

1 Like