bool trig;
bool load;
bool save;
uint32_t length;
uint32_t offset;
uint8_t bytes;
int rem_sz;

FILINFO fno;
DIR dir;
FIL FileObject;
FRESULT err;
UINT bytes_written;
UINT bytes_read;

// load file from SD:: fload (filename,destination table adress,start
// index,length)
void fload(const char *fn, char *table, int start, int bytes_rem)
    __attribute__((noinline)) {
  err = f_open(&FileObject, fn, FA_READ | FA_OPEN_EXISTING);
  if (err != FR_OK) {
    report_fatfs_error(err, fn);
    return;
  }
  int offset = 0;
  while (bytes_rem > 0) {
    if (bytes_rem > sizeof(fbuff)) {
      err = f_read(&FileObject, fbuff, sizeof(fbuff), &bytes_read);
      if (bytes_read == 0)
        break;
      memcpy(table + offset + start, (char *)fbuff, bytes_read);
      bytes_rem -= bytes_read;
      offset += bytes_read;
    } else {
      err = f_read(&FileObject, fbuff, bytes_rem, &bytes_read);
      memcpy(table + offset + start, (char *)fbuff, bytes_read);
      bytes_rem = 0;
    }
  }
  if (err != FR_OK) {
    report_fatfs_error(err, fn);
    return;
  }
  err = f_close(&FileObject);
}

// save array to SD::fsave (filename,source table adress,start index,length)
void fsave(const char *fn, char *table, int start, int bytes_rem)
    __attribute__((noinline)) {
  err = f_open(&FileObject, fn, FA_WRITE | FA_CREATE_ALWAYS);
  if (err != FR_OK) {
    report_fatfs_error(err, fn);
    return;
  }
  int offset = 0;
  while (bytes_rem > 0) {
    if (bytes_rem > sizeof(fbuff)) {
      memcpy((char *)fbuff, table + offset + start, sizeof(fbuff));
      err = f_write(&FileObject, fbuff, sizeof(fbuff), &bytes_written);
      bytes_rem -= sizeof(fbuff);
      offset += sizeof(fbuff);
    } else {
      memcpy((char *)fbuff, table + offset + start, bytes_rem);
      err = f_write(&FileObject, fbuff, bytes_rem, &bytes_written);
      bytes_rem = 0;
    }
  }
  if (err != FR_OK) {
    report_fatfs_error(err, fn);
    return;
  }
  err = f_close(&FileObject);
}

// get file length in 8-bit bytes::fsize (filename)
int fsize(const char *fn) __attribute__((noinline)) {
  err = f_open(&FileObject, fn, FA_READ);
  if (err != FR_OK) {
    report_fatfs_error(err, fn);
    return 0;
  } else {
    return f_size(&FileObject);
    err = f_close(&FileObject);
  }
}

bytes = sizeof(*attr_table.array);

if (inlet_load && !trig) {
  trig = 1;
  load = 1;
}
if (inlet_save && !trig) {
  trig = 1;
  save = 1;
}

if (load) {
  load = 0;
  int filesize = fsize(inlet_filename) / bytes;
  rem_sz = (((filesize + inlet_offset) > attr_table.LENGTH) ? attr_table.LENGTH
                                                            : filesize) *
           bytes;
  fload(inlet_filename, (char *)&attr_table.array[0], inlet_offset * bytes,
        rem_sz);
}
if (save) {
  save = 0;
  rem_sz = (((inlet_length + inlet_start) > attr_table.LENGTH)
                ? attr_table.LENGTH - inlet_start
                : inlet_length) *
           bytes;
  fsave(inlet_filename, (char *)&attr_table.array[0], inlet_start * bytes,
        rem_sz);
}

if (!inlet_load && !inlet_save)
  trig = 0;