This Arduino-Compatible Macropad Makes /fəˈnɛt ɪk/ Typing Easier

Pseudonymous maker "gm310509" has built an Arduino-compatible macropad with a difference: it's designed to make it easier to type phonetically, as part of an English learning course.

"My wife (who is Chinese) is taking an English class. A large part of this class is pronunciation — a large part of which is in written form. This means phonetics, or /fəˈnɛt ɪks/," gm310509 explains. "While you can type phonetic characters directly on Windows (and Mac) using complex patterns involving the numeric keypad it is cumbersome. So, I made this phonetic keypad for her birthday."

The keypad is powered by an Arduino Micro-compatible microcontroller, built around the Microchip ATmega32U4 — which includes built-in USB Human Interface Device (HID) capabilities, allowing it to present to the host system. This is wired to a 4×5 keyboard matrix, with anti-ghosting diodes preventing false actuation should multiple keys be pressed near-simultaneously, based on Cherry-style mechanical keyboard switches.

"As the keys are pressed on the keypad," gm310509 explains, "the code will generate the corresponding ALT-nnn sequence […] just as if it is typed on a 'real' keyboard. The end result is that the corresponding phonetic symbol appears in the Windows application that currently has focus (which would be MS-Word in my wife's case)."

The electronics, which are hand-wired in this initial incarnation, are housed in a custom 3D-printed chassis. "I am currently working on a PCB version," the maker explains, "which should fit in a much lower profile case."

More information on the project is available in gm310509's Reddit post.