Example Code for ESP32-Microphone Input Test

Hardware Preparation

• FireBeetle 2 ESP32-E IoT Microcontroller (SKU: DFR0654) × 1
• Fermion: I2S MEMS Microphone (SKU: SEN0526) × 1
• M-M/F-M/F-F Jumper wires

Software Preparation

• Download Arduino IDE: Click to download Arduino IDE.
• Install SDK: click to enter FireBeetle ESP32-E IoT Microcontroller Wiki for SDK installation tutorial.
• Download and install the DFRobot_MSM261.
• For Arduino IDE V1.8.19 (or earlier), install the library manually: How to Add a Library？
• For Arduino IDE V2.0.0 (or later), directly search for the "DFRobot_MSM261" in the Library Manager and install it.

Wiring Diagram

Pin Connections:

Other Preparation Work

Configure the microphone as receiving data of left channel by setting MODE_PIN (pin 4) to LOW.

Sample Code

ESP32-E initializes MSM261 I2S microphone (left channel, 44.1kHz), reads audio data and outputs via serial port.

#include "DFrobot_MSM261.h"

#define SAMPLE_RATE     (44100)
#define I2S_SCK_IO      (25)
#define I2S_WS_IO       (16)
#define I2S_DI_IO       (26)
#define DATA_BIT        (16)
#define MODE_PIN        (4)
DFRobot_Microphone microphone(I2S_SCK_IO, I2S_WS_IO, I2S_DI_IO);
char i2sReadrawBuff[100];
void setup() {
  Serial.begin(115200);//Serial rate 115200
  pinMode(MODE_PIN,OUTPUT);
  digitalWrite(MODE_PIN,LOW);//Configure the microphone as receiving data of left channel
  while(microphone.begin(SAMPLE_RATE, DATA_BIT) != 0){
      Serial.println(" I2S init failed");//Init failed
  }
  Serial.println("I2S init success");//Init succeeded
}

void loop() {
  microphone.read(i2sReadrawBuff,100);
  //Output data of left channel
  Serial.println((int16_t)(i2sReadrawBuff[0]|i2sReadrawBuff[1]<<8));
  delay(100);
}

Result

Blow into the microphone, and the corresponding peak & trough of the wave can be seen in the serial monitor.