Datasheet

If you open the Serial Monitor, you can see the values that are written to and read from each

GPIO pin.

Note that the GPIO pins are NOT 5v safe. Do not connect them to voltages greater than

3.3v.

https://learn.adafruit.com/adafruit-vs1053-mp3-aac-ogg-midi-wav-

play-and-record-codec-tutorial

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