Debug Features - Makuna/DFMiniMp3 GitHub Wiki

Mp3_Ack_API_Test.ino

This sketch will call every supported API from this library and is useful to diagnose support for your specific chipset. It uses the DfMiniMp3Debug debug feature listed below.
This sketch is found in the examples for this library under the extras folder. Note that Arduino IDE 2.0+ hides the extra folder, so you will need to search for it under the library location.

DfMiniMp3Debug

The DfMiniMp3Debug feature provides an ability to turn on low level debug output of the communications between the Arduino and the MP3 chip. This is useful in diagnosing communications errors or missing features with some MP3 chip sets.
To use the feature, you must be able to use a serial output for debug outputs. Most sketches will use Serial object for this very purpose, but the DfMiniMp3Debug feature doesn't require that it be that specific serial object, just one that you can capture the output on.
Just define the serial object you want to use before you include the library header file like the following.

#define DfMiniMp3Debug Serial
#include <DFMiniMp3.h>

This will then display the hex dump of the communications in the serial output like the following.

OUT  7e ff 06 48 00 00 00 fe b3 ef
IN  7e ff 06 48 00 03 e8 fd c8 ef

While you may not be able to make sense of this information, it is very useful to include in issues and discussions to help remotely troubleshoot problems.