Hi,
I'm currently working on a uni project in which I'm making a glove with piezo sensors on the fingertips that output a MIDI note into Ableton. I've found some example code in Arduino which works perfectly for one piezo, but I'm not sure how to change the code in a way that will allow five different piezos to output five different MIDI notes. I'll post the example code below for reference -
const int channel = 10; // General MIDI: channel 10 = percussion sounds
const int note = 36; // General MIDI: note 38 = acoustic snare
const int analogPin = A0;
const int thresholdMin = 60; // minimum reading, avoid noise and false starts
const int peakTrackMillis = 12;
const int aftershockMillis = 25; // aftershocks & vibration reject
void setup() {
Serial.begin(115200);
while (!Serial && millis() < 2500) /* wait for serial monitor */ ;
Serial.println("Piezo Peak Capture");
}
void loop() {
int piezo = analogRead(analogPin);
peakDetect(piezo);
// Add other tasks to loop, but avoid using delay() or waiting.
// You need loop() to keep running rapidly to detect Piezo peaks!
// MIDI Controllers should discard incoming MIDI messages.
// http://forum.pjrc.com/threads/24179-Teensy-3-Ableton-Analog-CC-causes-midi-crash
while (usbMIDI.read()) {
// ignore incoming messages
}
}
void peakDetect(int voltage) {
// "static" variables keep their numbers between each run of this function
static int state; // 0=idle, 1=looking for peak, 2=ignore aftershocks
static int peak; // remember the highest reading
static elapsedMillis msec; // timer to end states 1 and 2
switch (state) {
// IDLE state: wait for any reading is above threshold. Do not set
// the threshold too low. You don't want to be too sensitive to slight
// vibration.
case 0:
if (voltage > thresholdMin) {
//Serial.print("begin peak track ");
//Serial.println(voltage);
peak = voltage;
msec = 0;
state = 1;
}
return;
// Peak Tracking state: capture largest reading
case 1:
if (voltage > peak) {
peak = voltage;
}
if (msec >= peakTrackMillis) {
//Serial.print("peak = ");
//Serial.println(peak);
int velocity = map(peak, thresholdMin, 1023, 1, 127);
usbMIDI.sendNoteOn(note, velocity, channel);
msec = 0;
state = 2;
}
return;
// Ignore Aftershock state: wait for things to be quiet again.
default:
if (voltage > thresholdMin) {
msec = 0; // keep resetting timer if above threshold
} else if (msec > aftershockMillis) {
usbMIDI.sendNoteOff(note, 0, channel);
state = 0; // go back to idle when
}
}
}
Apologies if I've been confusing, coding and Arduino are still very new to me!
Any help is very greatly appreciated.
I'm currently working on a uni project in which I'm making a glove with piezo sensors on the fingertips that output a MIDI note into Ableton. I've found some example code in Arduino which works perfectly for one piezo, but I'm not sure how to change the code in a way that will allow five different piezos to output five different MIDI notes. I'll post the example code below for reference -
const int channel = 10; // General MIDI: channel 10 = percussion sounds
const int note = 36; // General MIDI: note 38 = acoustic snare
const int analogPin = A0;
const int thresholdMin = 60; // minimum reading, avoid noise and false starts
const int peakTrackMillis = 12;
const int aftershockMillis = 25; // aftershocks & vibration reject
void setup() {
Serial.begin(115200);
while (!Serial && millis() < 2500) /* wait for serial monitor */ ;
Serial.println("Piezo Peak Capture");
}
void loop() {
int piezo = analogRead(analogPin);
peakDetect(piezo);
// Add other tasks to loop, but avoid using delay() or waiting.
// You need loop() to keep running rapidly to detect Piezo peaks!
// MIDI Controllers should discard incoming MIDI messages.
// http://forum.pjrc.com/threads/24179-Teensy-3-Ableton-Analog-CC-causes-midi-crash
while (usbMIDI.read()) {
// ignore incoming messages
}
}
void peakDetect(int voltage) {
// "static" variables keep their numbers between each run of this function
static int state; // 0=idle, 1=looking for peak, 2=ignore aftershocks
static int peak; // remember the highest reading
static elapsedMillis msec; // timer to end states 1 and 2
switch (state) {
// IDLE state: wait for any reading is above threshold. Do not set
// the threshold too low. You don't want to be too sensitive to slight
// vibration.
case 0:
if (voltage > thresholdMin) {
//Serial.print("begin peak track ");
//Serial.println(voltage);
peak = voltage;
msec = 0;
state = 1;
}
return;
// Peak Tracking state: capture largest reading
case 1:
if (voltage > peak) {
peak = voltage;
}
if (msec >= peakTrackMillis) {
//Serial.print("peak = ");
//Serial.println(peak);
int velocity = map(peak, thresholdMin, 1023, 1, 127);
usbMIDI.sendNoteOn(note, velocity, channel);
msec = 0;
state = 2;
}
return;
// Ignore Aftershock state: wait for things to be quiet again.
default:
if (voltage > thresholdMin) {
msec = 0; // keep resetting timer if above threshold
} else if (msec > aftershockMillis) {
usbMIDI.sendNoteOff(note, 0, channel);
state = 0; // go back to idle when
}
}
}
Apologies if I've been confusing, coding and Arduino are still very new to me!
Any help is very greatly appreciated.
