test – Richard Gallon – MA Interactive Digital Media

ex-XBees

So…it seems that the combination of XBee RSSI data and the Mozzi synth can only produce intermittent or pulsing sound and doesn’t allow for constant tones, as witnessed by the following video demos. All the data that has to be sent from Arduino to the XBee in order to get it to send and receive packets is causing the audio to stutter.

To get the tones required for the final piece, the circuits will need to be created using SX1278 LoRa modules instead. These will connect the four Space Rocks via an additional transmitter, and based around this circuit:

This should guarantee that the Mozzi synths can play continuous tones rather than interrupted pulses. Although I’ll now need to find a way to fit 4+” 433MHz antennaes into the Space Rocks too.

Two more XBees talking

Node and co-ordinator: two synths talking

Finally have some code that changes the synths on the Space Rock sound modules, based on the distance between Rocks.

XBee synth - co-ordinator — XBee synth – co-ordinator

Space Rock stands

Some ideas for the stands for the Space Rocks. Plus revised drawing of exhibition set-up. The stands would be milled from wood.

Playing with Mozzi & XBee RSSI values to manipulate sound

Noise Generation. Playing with Mozzi & XBee RSSI values to manipulate sound. Note sound changes as RSSI feed connected to pin D5.

Organised chaos

Trying to keep track of the small things.

Using my own samples with Mozzi

Have finally cracked getting my own samples into Mozzi. The sound clips need to be VERY short (around 0.5 seconds) or they are too big for the Nano. I also tried mono to see if that saved space, but then there was no sound at all. I really raised the volume of this sample and the clipping isn’t too noticeable compared to the previously-encoded version , as it clips because of the processing anyway.

Here’s the code:

/*  Example of playing a sampled sound,
    using Mozzi sonification library.
  
    Demonstrates one-shot samples scheduled
    with EventDelay.
  
    Circuit: Audio output on digital pin 9 on a Uno or similar, or
    DAC/A14 on Teensy 3.1, or 
    check the README or http://sensorium.github.com/Mozzi/
  
    Mozzi help/discussion/announcements:
    https://groups.google.com/forum/#!forum/mozzi-users
  
    Tim Barrass 2012, CC by-nc-sa.
*/

#include <MozziGuts.h>
#include <Sample.h> // Sample template
#include <samples/alienwave.h>
#include <EventDelay.h>

#define CONTROL_RATE 64

// use: Sample <table_size, update_rate> SampleName (wavetable)
Sample <alienwave_NUM_CELLS, AUDIO_RATE> aSample(alienwave_DATA);

// for scheduling sample start
EventDelay kTriggerDelay;

void setup(){
  startMozzi(CONTROL_RATE);
  aSample.setFreq((float) alienwave_SAMPLERATE / (float) alienwave_NUM_CELLS); // play at the speed it was recorded
  kTriggerDelay.set(1500); // 1500 msec countdown, within resolution of CONTROL_RATE
}


void updateControl(){
  if(kTriggerDelay.ready()){
    aSample.start();
    kTriggerDelay.start();
  }
}


int updateAudio(){
  return (int) aSample.next();
}


void loop(){
  audioHook();
}