Microphone

Digital I/O
Analog I/O
Advanced I/O
Time
Math
Trigonometry
Random Numbers
Bits and Bytes
Interrupts
Serial Comm.

---

Camera
Servo Motor
Stepping Motor
Character LCD
SPI
I²C (Wire)
SD Card
SD (File Operations)
Periodic Operation
Clock (RTC)

---

Overview
Storage
Wi-Fi
TLS (HTTPS)
Audio
Microphone
BLE

This example shows how to input sound from the audio jack.

---

This example outputs the microphone input from the speaker.

#include <Arduino.h>

#include "AUDIO_GRBoard.h"
    
#define WRITE_BUFF_NUM         (16)
#define READ_BUFF_SIZE         (4096)
#define READ_BUFF_NUM          (16)
#define MAIL_QUEUE_SIZE        (WRITE_BUFF_NUM + READ_BUFF_NUM + 1)
#define INFO_TYPE_WRITE_END    (0)
#define INFO_TYPE_READ_END     (1)
    
AUDIO_GRBoard audio(0x80, WRITE_BUFF_NUM, READ_BUFF_NUM);
    
typedef struct {
    uint32_t info_type;
    void *   p_data;
    int32_t  result;
} mail_t;
Mail mail_box;
    
//32 bytes aligned! No cache memory
static uint8_t audio_read_buff[READ_BUFF_NUM][READ_BUFF_SIZE] __attribute((section("NC_BSS"),aligned(32)));
    
static void callback_audio(void * p_data, int32_t result, void * p_app_data) {
    mail_t *mail = mail_box.alloc();
    
    if (result < 0) {
        printf("error %ld\r\n", result);
    }
    if (mail == NULL) {
        printf("error mail alloc\r\n");
    } else {
        mail->info_type = (uint32_t)p_app_data;
        mail->p_data    = p_data;
        mail->result    = result;
        mail_box.put(mail);
    }
}
void setup() {
    rbsp_data_conf_t audio_write_conf = {&callback_audio, (void *)INFO_TYPE_WRITE_END};
    rbsp_data_conf_t audio_read_conf  = {&callback_audio, (void *)INFO_TYPE_READ_END};
    
    audio.power();
    audio.outputVolume(1.0, 1.0);
    audio.micVolume(0.7);
    
    // Read buffer setting
    for (int i = 0; i < READ_BUFF_NUM; i++) {
        if (audio.read(audio_read_buff[i], READ_BUFF_SIZE, &audio_read_conf) < 0) {
            printf("read error\r\n");
        }
    }
    
    while (1) {
        osEvent evt = mail_box.get();
        if (evt.status == osEventMail) {
            mail_t *mail = (mail_t *)evt.value.p;
    
            if ((mail->info_type == INFO_TYPE_READ_END) && (mail->result > 0)) {
                audio.write(mail->p_data, mail->result, &audio_write_conf);
            } else {
                audio.read(mail->p_data, READ_BUFF_SIZE, &audio_read_conf); // Resetting read buffer
            }
            mail_box.free(mail);
        }
    }
}
    
void loop() {
    
}
</mail_t,>