After all, the Arduino isn’t actually measuring the CPU speed, nor is it directly controlling it (that’s still done by the original Turbo button wiring).

The hardware — an Arduino Pro Micro and some buttons — should come as no surprise, except for maybe [memstra]’s use of a resistor network for the LEDs. Still, there’s a lot to like about ...

Running out of GPIO pins? Learn how to connect multiple buttons to just one Arduino pin using clever wiring and resistor techniques. Perfect for compact projects, keyboards, or when using small ...