SparkFun Forums 

Where electronics enthusiasts find answers.

Questions &/or issues related to products in the Audio category should be posted in this forum.
I'm wondering how to replicate the functions offered in the InitMaker app using Arduino's Serial protocol.
I’ve successfully begun controlling the WAV trigger with an Arduino using Serial by following the online guides. I’ve installed the 3 necessary libraries (Metro, AltSerial, and WAV-Trigger-Arduino-Serial) and gleaned from the basic example code how to get sounds to play. I’m using 4 sparkfun touch sensors (link below) outputting on/off data into the Arduino. I’m also powering the WAV trigger through the serial input from Arduino by soldering the 5v jumper.

Three of the sensors should activate one short audio clip each, without retriggering or looping, and one sensor should activate several random sounds, also without retriggering or looping. I had this all working well by using the init-maker app to generate a hex file for the SD card. Could I theoretically just load that same hex file onto the SD card and work with Arduino from there or would I need to write all my own custom Arduino code for controlling tracks in the same ways that InitMaker does? Not sure how exactly to write the code to get retriggering turned off, but I may be able to figure that out.

I’ve been referencing the WAV trigger Online User Guide’s “Serial Control Protocol” section and also the README note from the Github library page and can’t find the answers at this link: ... l-Library
These are the sensors I'm using:

And here's the code I have so far:
Code: Select all
// ****************************************************************************
//       Sketch: WTriggerUno
// Date Created: 4/22/2015
//     Comments: Demonstrates basic serial control of the WAV Trigger from an
//               Arduino.
//  Programmers: Jamie Robertson,
// To use this sketch, you'll need to:
// 1) Download + install the AltSoftSerial library.
// 2) Download + install the Metro library.
// 3) Connect 2 wires from the UNO to the WAV Trigger's serial connector:
//    Uno           WAV Trigger
//    ===           ===========
//    GND  <------> GND
//    Pin9 <------> RX
//    If you want to power the WAV Trigger from the Uno, then close the 5V
//    solder jumper on the WAV Trigger and connect a 3rd wire:
//    5V   <------> 5V

#include <Metro.h>
#include <AltSoftSerial.h>    // Arduino build environment requires this
#include <wavTrigger.h>

#define LED 13                // our LED

wavTrigger wTrig;             // Our WAV Trigger object

Metro gLedMetro(500);         // LED blink interval timer
//Metro gSeqMetro(6000);        // Sequencer state machine interval timer

byte gLedState = 0;           // LED State
//int  gSeqState = 0;           // Main program sequencer state
//int  gRateOffset = 0;         // WAV Trigger sample-rate offset

const int touch2 = 2;  // Input pins for touch state
const int touch3 = 3; // touch sensors are also pulled low to gnd with 10k resistors
const int touch4 = 4;
const int touch5 = 5;
int buttonState147 = 0; //initialize each button to LOW
int buttonState258 = 0;
int buttonState369 = 0;
int buttonStateR = 0;

// ****************************************************************************
void setup() { 
  Serial.begin(9600); // Serial monitor
  pinMode(LED,OUTPUT); // Initialize the LED pin

  // If Arduino is powering WAV Trigger, we should wait for the WAV
  //  Trigger to finish reset before trying to send commands.
  // WAV Trigger startup at 57600
  // Send stop-all command and reset the sample-rate offset, in case we have
  //  reset while the WAV Trigger was already playing.

  pinMode(touch2, INPUT);
  pinMode(touch3, INPUT);
  pinMode(touch4, INPUT);
  pinMode(touch5, INPUT);

void loop() {
  buttonState147 = digitalRead(touch2);
  buttonState258 = digitalRead(touch3);
  buttonState369 = digitalRead(touch4);
  buttonStateR = digitalRead(touch5);

  // If a touch is detected, turn on LED
  if (buttonState147 == HIGH) {
digitalWrite(LED, HIGH);    
wTrig.trackLoop(1, false); //this didn't help the retriggering issue either
delay(100); /*short delay to keep audio clips from distorting 
Short term solution while searching for way to keep audio 
from retriggerig*/

  } else {
    digitalWrite(LED, LOW);

 if (buttonState258 == HIGH) {
digitalWrite(LED, HIGH);    
wTrig.trackLoop(2, false);

  } else {
    digitalWrite(LED, LOW);

  if (buttonState369 == HIGH) {
digitalWrite(LED, HIGH);    
wTrig.trackLoop(3, false);

  } else {
    digitalWrite(LED, LOW);

  if (buttonStateR == HIGH) {
digitalWrite(LED, HIGH);    
wTrig.trackPlaySolo(random(4,7)); //will likely need to rewrite this using 'int i'


  } else {
    digitalWrite(LED, LOW);

Hi 0hm_mic_0dd,

This is a bit beyond the scope of SparkFun's Tech Support so we'll only be able to help with some tips. We cannot assist you with your code but I do have a few suggestions that may help you with this project. First, to help reduce any retriggering, you could try adding in some debouncing like this Arduino Tutorial demonstrates. You really should not need to worry about that with the Capacitive Touch breakout since it provides a pretty clean HIGH/LOW signal compared to a physical button but that code will help prevent retriggering if the pad is touched accidentally.

The INI file will be necessary to tell the WAV Trigger how each trigger should function and from there, you can either tie a digital I/O pin on your Arduino to a trigger pin on the WAV Trigger or send serial commands using the Arduino library depending on the input from one of your touch sensors. The ReadMe section on the WAV Trigger Arduino Serial Library has some great descriptions for how to use each function. You may want to start simple (eg. 1 touch sensor input calling the "wTrig.trackPlaySolo(int t);" function) and then build from there. Doing this in steps will help you debug where any issues are originating from.

I hope this helps you progress with this project. If you run into any other issues or have other questions about the WAV Trigger or the Capacitive Touch breakout, let us know and we would be happy to help as much as we can.