sonometre.ino
The microphone returns ambient amplitude: clap and watch the LED pulse. This is the basis of air instruments and noise detectors, with no external part.
Hardware required
An Arduino Esplora (ATmega32U4, 5 V) with its onboard sensors: joystick, 4 buttons, slider, RGB LED, buzzer, light, temperature, sound and accelerometer. None.
Wiring
Nothing to wire; get close to test.
How it works
readMicrophone samples the mic; the raw value maps to RGB LED brightness. In the Arduino IDE, select « Arduino Esplora »; add the « Esplora » library from the Library Manager to reach the onboard sensors.
Going further
Trigger a melody on a clap (threshold + timeout), or log the sound envelope over serial.
sonometre.ino
// Microphone embarque -> niveau sonore en serie + pulsation lumineuse.
#include <Esplora.h>
void setup() {
Serial.begin(9600);
}
void loop() {
int v = Esplora.readMicrophone(); // 0..1023
Serial.println(v);
int lueur = map(v, 0, 1023, 0, 255);
Esplora.writeRGB(lueur, lueur / 2, 0); // pulsation chaude sur le bruit
delay(20);
}