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insane
07-29-2016, 02:39 AM
It's very nice working with the Audio System Design Tool, but I've run into a problem that stumps me. I'm trying to combine a couple of concepts from the Audio Workshop Tutorial that don't seem to work--well, I'm sure there's way; I just can't figure it out!

So I'm using a Teensy 3.2 with an Audio Shield and the 1.6.8 Arduino IDE.

The objective is to select either an audio file from the SD card (on the shield), play a guitar clip from RAM, or play a generated tone--this is pretty-much straight from the Tutorial. Additionally, I want to patch the output to FFT, but first pass it through low-pass and high-pass filters. Each of these is again separately borrowed from the workshop Tutorial. My twist is that besides sending the FFT data to the serial monitor, I'm lighting up an Adafruit NeoPixel strip with it. All this works well, separately.

The problem is that when I put it all together, there is no sound output. However, if I comment out the patchCord to the FFT object in the Design Tool, then sound plays--but obviously without FFT data.

Here's the source code and Design Tool image--should look pretty familiar:


7765



#include <Adafruit_NeoPixel.h>
#ifdef __AVR__
#include <avr/power.h>
#endif

#define PIN 3
#define NUMPIXELS 30

#include "AudioSampleGuitar.h"
#include <Bounce.h>

Bounce button0 = Bounce(0, 15);
Bounce button1 = Bounce(1, 15);
Bounce button2 = Bounce(2, 15);

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

///////////////////////////////////
#include <Audio.h>
//#include <Wire.h>
//#include <SPI.h>
//#include <SD.h>
//#include <SerialFlash.h>

// GUItool: begin automatically generated code
AudioPlayMemory playMem1; //xy=87.19999694824219,134.1999969482422
AudioSynthWaveform waveform1; //xy=91.19999694824219,194.1999969482422
AudioPlaySdWav playSdWav1; //xy=94.19999694824219,69.19999694824219
AudioMixer4 mixer1; //xy=303.20001220703125,50.19999694824219
AudioFilterStateVariable filter1; //xy=389.20001220703125,139.1999969482422
AudioMixer4 mixer2; //xy=504.20001220703125,234.1999969482422
AudioFilterStateVariable filter2; //xy=522.2000122070312,138.1999969482422
AudioAnalyzeFFT1024 fft1024_1; //xy=714.2000122070312,217.1999969482422
AudioOutputI2S i2s1; //xy=717.2000122070312,124.19999694824219
AudioConnection patchCord1(playMem1, 0, mixer1, 2);
AudioConnection patchCord2(waveform1, 0, mixer1, 3);
AudioConnection patchCord3(playSdWav1, 0, mixer1, 0);
AudioConnection patchCord4(playSdWav1, 1, mixer1, 1);
AudioConnection patchCord5(mixer1, 0, filter1, 0);
AudioConnection patchCord6(filter1, 2, filter2, 0);
AudioConnection patchCord7(mixer2, 0, i2s1, 0);
AudioConnection patchCord8(mixer2, 0, i2s1, 1);
AudioConnection patchCord9(mixer2, fft1024_1); // <---
AudioConnection patchCord10(filter2, 0, mixer2, 0);
AudioControlSGTL5000 sgtl5000_1; //xy=264.20001220703125,272.20001220703125
// GUItool: end automatically generated code
///////////////////////////////////


void setup() {
Serial.begin(9600);
pixels.begin(); // This initializes the NeoPixel library.
pixels.show(); // Initialize all pixels to 'off'

AudioMemory(10);
sgtl5000_1.enable();
sgtl5000_1.volume(0.5);

SPI.setMOSI(7);
SPI.setSCK(14);
if (!(SD.begin(10))) {
while (1) {
Serial.println("Unable to access the SD card");
delay(500);
}
}
pinMode(0, INPUT_PULLUP);
pinMode(1, INPUT_PULLUP);
pinMode(2, INPUT_PULLUP);
mixer1.gain(0, 0.5); // soundwave L
mixer1.gain(1, 0.5); // soundwave R
mixer1.gain(2, 0.0); // memory
mixer1.gain(3, 0.0); // waveform
mixer2.gain(0, 1.0); // filtered audio
mixer2.gain(1, 0.0);
mixer2.gain(2, 0.0);
mixer2.gain(3, 0.0);
filter1.frequency(80);
filter2.frequency(9000);
delay(1000);
playSdWav1.play("SDTEST1.WAV");
}

int fileNumber = 0;
const char * filenames[4] = {
"SDTEST1.WAV", "SDTEST2.WAV", "SDTEST3.WAV", "SDTEST4.WAV",
};

int noteNumber = 0;
const float noteFrequency[49] = {
440.00, // A
466.16, // A#
493.88, // B
523.25, // C
554.37, // C#
587.33, // D
622.25, // D#
659.26, // E
698.46, // F
739.99, // F#
783.99, // G
830.61, // G#
};


void loop() {
if (fft1024_1.available()) {
Serial.print("FFT: ");
for (int i=0; i<30; i++) {
float n = fft1024_1.read(i);
printNumber(n);
pixels.setPixelColor(i, pixels.Color(0, n*1000 ,0));
}
pixels.show(); // This sends the updated pixel color to the hardware.
Serial.println();
}

button0.update();
button1.update();
button2.update();

// Left button starts playing a new song
if (button0.fallingEdge()) {
mixer1.gain(2, 0.0);
mixer1.gain(3, 0.0);
fileNumber = fileNumber + 1;
if (fileNumber >= 10) fileNumber = 0;
playMem1.stop();
playSdWav1.play(filenames[fileNumber]);
mixer1.gain(0, 0.5);
mixer1.gain(1, 0.5);
}

// Middle button plays Guitar sample
if (button1.fallingEdge()) {
mixer1.gain(0, 0.0);
mixer1.gain(1, 0.0);
mixer1.gain(3, 0.0);
playSdWav1.stop();
playMem1.play(AudioSampleGuitar);
mixer1.gain(2, 1.0);
}

// Right button plays a pure sine wave tone
if (button2.fallingEdge()) {
mixer1.gain(0, 0.0);
mixer1.gain(1, 0.0);
mixer1.gain(2, 0.0);
playSdWav1.stop();
playMem1.stop();
waveform1.begin(1.0, noteFrequency[noteNumber], WAVEFORM_SINE);
noteNumber = noteNumber + 1;
if (noteNumber >= 49) noteNumber = 0;
mixer1.gain(3, 1.0);
}
if (button2.risingEdge()) {
waveform1.amplitude(0);
}

// read the knob and adjust the filter frequency
int knobL = analogRead(A2);
int knobH = analogRead(A3);
// quick and dirty equation for exp scale frequency adjust
float freqL = expf((float)knobL / 150.0) * 10.0 + 80.0;
float freqH = expf((float)knobH / 150.0) * 10.0 + 80.0;
filter1.frequency(freqL);
filter2.frequency(freqH);
Serial.print("low frequency limit = ");
Serial.println(freqL);
Serial.print("high frequency limit = ");
Serial.println(freqH);
delay(200);
}

void printNumber(float n) {

if (n >= 0.004) {
Serial.print(n, 3);
Serial.print(" ");
} else {
Serial.print(" - "); // don't print "0.00"
}
}

Frank B
07-31-2016, 06:32 PM
tried to increase
AudioMemory(10);

?

insane
07-31-2016, 08:29 PM
tried to increase
AudioMemory(10);

?

I did not even think to try that; kinda makes sense, though. Have you had some sort of experience to the effect, or is it an educated guess?

I'll try it on Monday when I get back to the lab. Thanks.

-Michael (insane)

insane
08-01-2016, 07:02 PM
I did not even think to try that; kinda makes sense, though. Have you had some sort of experience to the effect, or is it an educated guess?

I'll try it on Monday when I get back to the lab. Thanks.

-Michael (insane)

Wow...it worked. I bumped AudioMemory from 10 to 20 and it worked. Thanks, man.