This feature isn’t exclusive to the Leonoardo, as [Michael] explains in a build he sent in – the lowly Arduino Uno can also serve as a USB HID keyboard with just a firmware update.

His offering uses the Arduino Uno, but there are several other hardware options covered as well. The firmware makes use of the serprog-duino library which was crafted at writing to flash memory chips.

The Arduino designers freely share the specifications for anyone to use, however, and third-party manufacturers all over the world offer versions of their own, sometimes optimized for specific ...