He also describes how it then processes the audio, applying a graphic equalizer ... including board gerbers and the STM32 firmware are available at the bottom of his post, and to boot, a video ...
Audio functionality is provided externally ... For STM32Boy, [Jan] uses the LCD screen that’s on the STM32 development board to render the screen on, along with a Game Boy skin.
The MCU adds ML to small, power-efficient devices, allowing AI features like computer vision, audio processing, & real-time ...