playing mp3 with very few pins

Projects General Guidance
1

Hi all,

I'm looking for a way to play mp3's through headphones, controlled by an Arduino Uno, but using only a few pins. I know that the popular mp3 player shield needs five (specific) pins to function (SparkFun MP3 Player Shield - DEV-12660 - SparkFun Electronics), but I would like to play mp3's in an application where I need those pins, most importantly the PWM pins, for other functions. So I have only one PWM pin left, and 3 other non-PWM pins. Does anyone know of a solution where only a few pins are sufficient, like a mp3 player that can be controlled over a serial connection? I found this audio shield, which works that way and only needs three pins, but it is to synthesize sound rather than to play pre-recorded sounds (www.ginsingsound.com). Any help appreciated!

2

Do you know that the analogue pins can be used as digital input / output pins as well?

3

Thanks, that's a helpful tip. No PWM on those unfortunately.

4

Here's a great option:
http://www.mdfly.com/index.php?main_page=product_info&cPath=9_53&products_id=284&zenid=cm69ckjevu8afqh5pkb9n6pmm1

I use lots of these. They're dead easy to interface with, and you can communicate with serial, meaning only 1 pin.

I've never had a problem with any of the 50+ I've used.

5

Great, that's exactly what I'm looking for! Did you ever use these with headphones? Is the signal strong enough to just hook up the outputs to headphones, or is an extra amp needed?
Thanks!

6

Also, do you know if that's the same module as this one? http://www.warf.com/download/5029_9878_TDB380%20datasheet%20V2.1%20.pdf
It looks the same in the image, but the listed specs are quite different.

7

That is in fact the same one.

In regards to headphones, I have used it with headphones alone, and had success, but it depends on the characteristics of the headphones to be sure.

8

Yes thanks, I also asked the shop and they said it's the same, but as they haven't tested all the features they advertise it with the tested features only.
By the way, did you use 50+ mp3-players for one project or were you building a line of products? Just curious :slight_smile:

9

That's been over the course of a year or two in many different projects. Most of them reasonably similar :slight_smile: