Home Forums Sparkfun MP3 Shield Library Support Forum Problems with Sparkfun MP3 straight from the box Reply To: Problems with Sparkfun MP3 straight from the box


Thank you very much for the quick reply Michael! 🙂

I have run some tests to clarify what is happening.

Sine-wave test:

Loud and clear and annoying if left on for too long.

Memory test:

“Memory test result: 83FF. Result should be 0x83FF.” As far as I understand, this is what we want.


Changed USE_MP3_REFILL_MEANS from USE_MP3_INTx to USE_MP3_Polled and back. Tried showing SD-card directory and play track with both. With INTx, same behavior as reported before, with Polled, SD-card directory does not show, and no track can be played.

DREQ logic levels:

I did some tests on the DREQ pin using my multimeter, and observed some strange behavior. Note that it is a low-end multimeter, so this is not tick by tick readings, more like second by second.

Startup: 3.3 V.
Running tests (d, m, t): 3.3 V
Start playing track: Drops quickly to about 1.4 V before stopping music and settling steady at 1.84 V. This part seems strange to me, as I was expecting 0 V or 3.3 V. It stays at 1.84 V until I issue another command.
From there, sending ‘i’: Drops to 0 V before going back to 3.3 V, stopping the music and refusing any more commands until I reset the system.
From there, sending ‘iiiii…’: Drops to 0 V and stays there spiking a bit every now and then until track is finished, then returns to menu and functions like normal. (I.e. after a reset)
This does however just happen with one of the tracks. (The one with bells from Sparkfun). The short track (drums) only plays the one second, then freezes the system no matter what I do. I suspect this being related to the fact that it is so short.

I don’t really know how to test whether the INT1 is occurring properly, but if you would advise me how I can test that too.

In my opinion, something seems to be rather wrong with the DREQ. Do you think this is a reasonable assumption? I am also wondering if this means that the board if broken, or just something else causing it?

Thank you again for all your help, it is most appreciated!

Have a nice day! 😀