Play mp3

Using Arduino Audio
1

Hi, im making a class project and i need some help about playing mp3 files with arduino.

I would like play only one music track, use one sensor and one dc motor, everything on an Arduino UNO shield. I was taking a look on music shield (Seeed/Sparkfun), but im not sure if it use all of the PWM pins for his own work.

I saw this too: SimpleSDAudio – Hackerspace Ffm
Its possible work with this example using Mac?

what you recomend me?

Thank you very much

2

can you say to me what hardware is used here?

3

That project uses PWM to emulate an audio waveform. That PWM signal is passed through a low-pass filter to remove the high frequency switching signal and leave an approximation of an audio waveform behind.

It'll be "average" at best. Also, it uses about 80% of the Arduino's available RAM just to run the audio, and integrating it with other things will be tricky as it needs to run its worker function all the time.

4

Thanks Majenko. Do you think that i will have the same power problem using one shield like this: SparkFun MP3 Player Shield - DEV-12660 - SparkFun Electronics?

5

That shield is a kind of half-way house.

It still uses the Arduino to read the mp3 data from the SD card and send it to the mp3 decoder chip, but because mp3 data is so heavily compressed there is much less data involved, and so the Arduino is more available for doing other things. Audio quality will be considerably better than a low-pass filtered PWM signal generated by the Arduino, but not as high quality as an uncompressed format player (purely because mp3 is a lossy codec, so you lose audio definition with it).

6

Thank you again Majenko!

But im wondering one new question... Okey, this shield gives more range to Arduino for works on other things while the first is playing the audio, but how this schema shows: http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Dev/Arduino/Shields/MP3%20Shield-v13.pdf
This music shield use all the grounds and the 5V pin too. It would be possible feed a motor and this shield at same time?

Thank you very much!!

7

Yes. You can connect as many devices in parallel to the power and ground pins as the current limit of the power source / voltage regulator will allow.

How you connect the wires is up to you - you could solder direct to the shield's ground and 5V pins, or insert a prototyping shield in between with stackable headers, etc.