Black Box engineering. You can add the 555 Timer to an already completed design if it is later discovered that debouncing was an unsolved problem. I don't thi

Black Box engineering. You can add the 555 Timer to an already completed design if it is later discovered that debouncing was an unsolved problem. I don't think it is always appropriate to assume that code can be rewritten (or rearchitected) to fit your needs. Sometimes its easier to solve problems with a touch of extra external hardware.