[analog31]

I made such a thing using a board called "Teensy LC." I'm a long time user of Teensy boards for prototyping in an R&D environment, and the LC is the cheapest. My interest was just PgUp and PgDn buttons for a foot pedal page turner.

In addition, I programmed an ESP32 board to do the same thing, but as a Bluetooth keyboard. Both the Teensy and ESP32 can be programmed via the Arduino development environment.

Now there's cheap and there's cheap. The stuff I use is cheap in terms of, it won't break the bank for a R&D or hobby project. Then there's cheap in terms of wringing cost out of a commercial product, which I know little to nothing about.

[HeyLaughingBoy]

> Then there's cheap in terms of wringing cost out of a commercial product

This is a very astute distinction that hobbyists wanting to go from Arduino to production often miss.

I went from the basically cost-unconstrained world of Medical Devices to wearable consumer sensors (e.g., heart rate monitors, etc.) and it was a bit of a shock to see just how much impact cost had. I mean, you know that in a "theoretical" sense, but it's completely different when you are dealing with it on a daily basis.