I developed a version where the TTL logic was replaced by a CPLD. This made the circuit much smaller. Instead of the Arduino Nano I directly integrated an ATMega32u4. This is flashed with the ...

In recent years, integrated platforms equipped with microcontrollers (with Arduino probably being the best-known brand) have been gaining popularity.

The Dabao open-source hardware board features a Boachip-1x RISC-V MCU, whose RTL Verilog files are also open, and is IRIS inspectable.