File content as of revision 4:01651a6c3f9a:

#include "mbed.h"
#include "TLV320_RBSP.h"
#include "USBHostMSD.h"
#include "dec_wav.h"

#if defined(TARGET_RZ_A1H)
#include "usb_host_setting.h"
#else
#define USB_HOST_CH     0
#endif

#if (USB_HOST_CH == 1) //Audio Shield USB1
DigitalOut usb1en(P3_8);
#endif
DigitalIn  button(USER_BUTTON0);

#define AUDIO_WRITE_BUFF_SIZE  (4096)
#define AUDIO_WRITE_BUFF_NUM   (9)
#define FILE_NAME_LEN          (64)
#define TEXT_SIZE              (64 + 1) //null-terminated
#define FLD_PATH               "/usb/"

//4 bytes aligned! No cache memory
static uint8_t audio_write_buff[AUDIO_WRITE_BUFF_NUM][AUDIO_WRITE_BUFF_SIZE]
                __attribute((section("NC_BSS"),aligned(4)));
//Tag buffer
static uint8_t title_buf[TEXT_SIZE];
static uint8_t artist_buf[TEXT_SIZE];
static uint8_t album_buf[TEXT_SIZE];

TLV320_RBSP audio(P3_13, P10_13, I2C_SDA, I2C_SCL, P4_4, P4_5, P4_7, P4_6,
                  0x80, (AUDIO_WRITE_BUFF_NUM - 1), 0);

static void callback_audio_write_end(void * p_data, int32_t result, void * p_app_data) {
    if (result < 0) {
        printf("audio write callback error %d\n", result);
    }
}

int main() {
    rbsp_data_conf_t audio_write_async_ctl = {&callback_audio_write_end, NULL};
    FILE * fp = NULL;
    DIR  * d = NULL;
    char file_path[sizeof(FLD_PATH) + FILE_NAME_LEN];
    int buff_index = 0;
    size_t audio_data_size;
    dec_wav wav_file;

    audio.power(0x02); // mic off
    audio.inputVolume(0.7, 0.7);

    USBHostMSD msd("usb");

    while(1) {
        // try to connect a MSD device
        while(!msd.connect()) {
            Thread::wait(500);
        }

        // in a loop, append a file
        // if the device is disconnected, we try to connect it again
        while(1) {
            // if device disconnected, try to connect again
            if (!msd.connected()) {
                break;
            }
            if (fp == NULL) {
                // file search
                if (d == NULL) {
                    d = opendir(FLD_PATH);
                }
                struct dirent * p;
                while ((p = readdir(d)) != NULL) {
                    size_t len = strlen(p->d_name);
                    if ((len > 4) && (len < FILE_NAME_LEN)
                        && (memcmp(&p->d_name[len - 4], ".wav", 4) == 0)) {
                        strcpy(file_path, FLD_PATH);
                        strcat(file_path, p->d_name);
                        fp = fopen(file_path, "r");
                        if (wav_file.analyze_heder(title_buf, artist_buf, album_buf,
                                                   TEXT_SIZE, fp) == false) {
                            fclose(fp);
                            fp = NULL;
                        } else {
                            printf("File  :%s\n", p->d_name);
                            printf("Title :%s\n", title_buf);
                            printf("Artist:%s\n", artist_buf);
                            printf("Album :%s\n", album_buf);
                            printf("\n");
                            break;
                        }
                    }
                }
                if (p == NULL) {
                    closedir(d);
                    d = NULL;
                }
            } else {
                // file read
                uint8_t * p_buf = audio_write_buff[buff_index];

                audio_data_size = wav_file.get_next_data(p_buf, AUDIO_WRITE_BUFF_SIZE);
                if (audio_data_size > 0) {
                    audio.write(p_buf, audio_data_size, &audio_write_async_ctl);
                    buff_index++;
                    if (buff_index >= AUDIO_WRITE_BUFF_NUM) {
                        buff_index = 0;
                    }
                }

                // file close
                if ((audio_data_size < AUDIO_WRITE_BUFF_SIZE) || (button == 0)) {
                    fclose(fp);
                    fp = NULL;
                    Thread::wait(500);
                }
            }
        }

        // close check
        if (fp != NULL) {
            fclose(fp);
            fp = NULL;
        }
        if (d != NULL) {
            closedir(d);
            d = NULL;
        }
    }
}