For Arduino AVR you'll need to build an 8-bit resistor DAC (e.g. resistor ladder) connected to data pins 0-7. To use Teensy Audio Shield change the following define from 0 to 1 in the beginning of pmf ...

How to link the DFPlayer MP3 player to an Arduino. Let the music play! This module can most certainly be used as a custom, Arduino-controlled player of music (in a pub or restaurant, for example) but ...

Arduino has also upgraded the onboard flash storage pool. The Uno R4 features 256 kilobytes of solid-state memory, eight times more than the previous-generation chip.