Asked — Edited

Mp3 Trigger - Set Volume

Hi DJ,

Hope your having fun at Maker Faire.

I finally got my MP3 Trigger in from Sparkfun.

It's up and running.

A question, maybe I'm missing it in ARC or it's not possible.

  1. Is there any command line to set volume for the MP3 Trigger? All I can find is the drop down on the MP3 Trigger control panel. I do not want to run external triggers to control volume.

Would it be possible to add a command line like this to EZ-Script?

MP3TriggerPlayTrack( d0, 38400, 6, 1 )

MP3TriggerPlayTrack( digitalPort, baud, volume, trackNumber ) Plays the specified MP3 track from the MP3 Trigger Shield, sets the volume for that individual track.


MP3TriggerVolume( d0, 38400, 6 )

MP3TriggerPlayVolume( digitalPort, baud, volume ) Sets MP3 Trigger volume. Range 0-6. 6= Loudest

I'm no programmer and have no idea if this is doable?

I'd like to be able to voice commands to set volume levels.

Eg: Robot Set Volume 4

And also specify volumes for specific tracks.

Let me know id this is doable or not. It would sure be nice to have.

I know your away, so maybe we can discuss when your back.



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Lumpy - I believe the you might be able to do some of what you want with the ini file features of the MP3 trigger board. Make sure you read the following site : This is the site of the board designer and contains way more helpful info than just the sparkfun site. Also read the instructions in the sample ini file.

BTW - I managed to fry my MP3 board - though I am not sure how... power light works - but no status light at all - can't even re-flash the board's firmware. This is a v2 board that has been discontinued - so I have ordered the newer version and will wait for it to arrive.



You can set volume in the .ini but it's for "all" if I've read it correctly.

I believe you can send serial commands to control volume but I do not know how.

I'm looking to set volume on an individual basis.

I've read all the files, and upgraded to latest firmware. Just not as technical on the programming side of things.


No - you can set individual volumes in the ini file - but for the trigger files. I am not sure if EZB calls on the trigger files - I think it just plays all files as tracks and would ignore the ini volume settings - but you could experiment with it. >>> #TRIG N, F, L

where: N is the trigger number (1 - 18)
       F is the trigger function type (see below)
       L is the restart lockout enable (see below)

The defined trigger function types (F) are as follows:

F = 0: Normal operation
F = 1: Next (same as the forward Nav switch)
F = 2: Random
F = 3: Previous (same as the back Nav switch)
F = 4: Start (restarts the current track)
F = 5: Stop
F = 6: Volume Up
F = 7: Volume Down

The restart lockout feature, if enabled, will prevent that trigger
from working if audio is currently playing. Use this if you want
to prevent restarts before the track has reached the end. This
feature does not apply to function types 5 - 7.

L = 0: Restart lockout disabled (default)
L = 1: Restart lockout enabled

Unfortunately I am not much of a help but if you always want the files to be different volumes I might have a work around. Depending on your applications. For exp.

I have different sounds that some I wanted lower and others to be a higher volume. I changed them in itunes prior to loading on my card. It actually worked pretty good.


Thanks sfoy. I could "normalize" them to all be at the same level.

I want to be able to change volume on the fly for conventions and such.


Oh yeah different application. GL


Tried using the SendSerial command and the codes mentioned in the MP3 Trigger documentation.

That was a no go.

Hoping it's just something simple.


i'll add it to the list.

in the meantime, use the SendSerial command and reference the documentation:)


Damn you and your smiley!:D I tried using the SendSerial and documentation. I failed at it. lol

In your example you use SendI2C(Port, Data, ...)

I tried SendMP3Trigger but it doesn't work. Couldn't figure out what command to send.

Tried SendMP3Trigger(d7, 38400, 0x00) but it doesn't like it.

I'm no programmer. :(

Help me DJ #1 You're my only hope!