For those into home-brew programming projects, its easy to make a microcontroller spit out some Morse code with the post shown below. What makes [pavlin’s] take on this project interesting is that it resides on a tiny USB board with an ARM processor. The design for the board is available with single-sided artwork suitable for production using simple methods like toner transfer.
The STM device has a built-in USB bootloader. It can also act as a serial port, which makes the project very simple and a bit more flexible. The only external parts are a speaker and an opt-oisolator.
The program provides a command line interface over the serial port that you can use to program the message and set other options like speed and the delay between messages.Continue Reading