How to Play Random Tracks on MP3 Trigger Board

Sensors Sound & Audio
1

Greetings,

I’m using the MP3 trigger board ( MP3 Trigger Hookup Guide V24 - SparkFun Learn ). I haven’t found any documentation on using the Random trigger function (02), as referenced in the Hookup Guide.

I want the board to play a random track when trigger 01 is activated. All files are named with the convention specified in the documentation (001.*mp3, etc.). Currently, when trigger 01 is activated the board will play 001*.mp3, but triggering again will play the same song, not a random song.

I have trigger 18 jumped to ground and set as a STOP trigger in the INI file.

My INI file:

#TRIG 01,2,0

#TRIG 18,5,0

Any useful advice is appreciated.

2

There’s been a similar case a few years back

Try this:

  1. Back up everything from the microSD card if needed

  2. Format the card as FAT32

  3. Copy the MP3 files back individually, in numerical order:

    001 something.mp3
002 something.mp3
003 something.mp3
004 something.mp3

  4. Copy MP3TRIGR.INI onto the card afterward

  5. Eject the card, put back into MP3 Trigger

  6. Test Trigger 01 several times. I would also temporarily remove Trigger 18 from the equation and test with just:

#TRIG 01,2,0

Once random selection works, add

#TRIG 18,5,0

back in :slight_smile:

Side note: #RAND isn’t required. #TRIG 01,2,0 already makes Trigger 01 the random trigger. #RAND N is an additional option that excludes the first N tracks in the directory from the random selection.

So, for example:

#RAND 1
#TRIG 01,2,0

would exclude the first file in the directory from the random pool. You don’t want that if 001 should be eligible :wink:

There’s also more info in the guide

3

I really appreciate your thorough reply. I certainly took the time to read the entire guide, everything on the Robertsonics site and all the forum posts I could find. I didn’t find the information I needed anywhere.

I solved this problem yesterday. I got an email from Robertsonics that reiterated the newer firmware version available. I made the bad assumption that because I bought a board recently I would get the latest firmware. That apparently wasn’t the case. I have included my log below, but basically I was able to accomplish Trigger 1 plays a random track every time it is triggered and stops at the end of the track. The track can be interrupted by triggering again. The track does not loop if Trigger 1 remains HIGH/active.

INI file:

#TRIG 01, 2, 0

All files are named according to the protocol, 001.mp3, 002.mp3, etc.

As you said, the #RAND wasn’t necessary. The STOP command on pin 18 also wasn’t necessary. I just have a switch wired to pin 1 and ground.

The latest firmware can be found at the bottom of the Robertsonics website:

https://www.robertsonics.com/downloads/

Log:

***First attempt:

#RAND
#TRIG 01, 2, 0
#TRIG 18, 5, 0

Tracks named with 001, 002, etc.
Formatted card, added songs one at a time, in order, ini first
–Some files were WAVs; trigger not activating (no LED indicator when activated); no sound output

***Second attempt:

#RAND

Tracks named with 001, 002, etc.
Formatted card, added songs one at a time, in order, ini first
–Trigger 01 works; plays track named 001 every time; no random; audio stops after 001 is played

***Third attempt:

#TRIG 01, 2, 0

Tracks named with 001, 002, etc.
Modified ini while on the card; left files on card (no format)
–Trigger 01 works; playes track 001 every time; no random; audio stops after 001 is played; no loop, even if trigger is constant on

***Fourth attempt:

Downloaded and updated firmware on board.
Repeated first attempt exactly with new firmware
–Trigger 01 works; plays track 001 every time; no random; no restart lockout - track restarts every time trigger is activated; audio stops after 001 is played

***Fifth attempt:
Repeated second attempt with new firmware
–Exact same as fourth attempt

***Sixth attempt:
Repeated third attempt exactly with new firmware

#TRIG 01, 2, 0
All tracks named with 001*.mp3, etc.

--Works! Trigger 01 plays a random track every time it is activated; audio stops when track is complete, even if trigger is active; no restart lockout; interruption of track plays next random track (sometimes repeats same “random” track order if trigger is activated too soon - less than 1 second)

4

The next item I have to solve is this:

I have a touchtone phone. I pick up the handset and a track starts playing. While the track is still playing, I want the buttons to play touchtones without the track stopping.

I’m thinking I’ll need a different solution for this. I didn’t read anything in the documentation about simultaneous triggering like this.

Do you think it’s possible with the MP3 trigger? If not, do you think I should go with a dedicated touchtone generator chip or is there something like the WAV trigger that would work?

5

Robertsonics knows all the tricks! Glad to hear that part is working

To play two or more sounds simultaneously you’re after a polyphonic device (3 are in stock), 14 for the WAV Trigger, 24 for the WAV Trigger Pro, 31 for the instrument shield