How to sync usb device MSC with host
I'm already achieved a USBX-MSC class, and also a FileX in MCU local.
I know that using two file systems at the same time is not recommended, but still have some questions.
1. I implement the ux_deveice_msc.c as followed. Use PC-Windows to create a file such as my_test.txt to U-DISK, successfully and the local FileX will see the new file immediately.
UINT USBD_STORAGE_Read(VOID *storage_instance, ULONG lun, UCHAR *data_pointer,
ULONG number_blocks, ULONG lba, ULONG *media_status)
{
UINT status = UX_SUCCESS;
/* USER CODE BEGIN USBD_STORAGE_Read */
UINT fxStatus = FX_SUCCESS;
while (number_blocks--) {
fxStatus = fx_media_read(sdioDisk, lba, data_pointer);
if (fxStatus != FX_SUCCESS) {
status = UX_ERROR;
break;
}
data_pointer += sdioDisk->fx_media_bytes_per_sector;
lba++;
}
/* USER CODE END USBD_STORAGE_Read */
return status;
}
UINT USBD_STORAGE_Write(VOID *storage_instance, ULONG lun, UCHAR *data_pointer,
ULONG number_blocks, ULONG lba, ULONG *media_status)
{
UINT status = UX_SUCCESS;
/* USER CODE BEGIN USBD_STORAGE_Write */
UINT fxStatus = FX_SUCCESS;
while (number_blocks--) {
fxStatus = fx_media_write(sdioDisk, lba, data_pointer);
if (fxStatus != FX_SUCCESS && lba != 0) {
status = UX_ERROR;
break;
}
data_pointer += sdioDisk->fx_media_bytes_per_sector;
lba++;
}
/* USER CODE END USBD_STORAGE_Write */
return status;
}
UINT USBD_STORAGE_Flush(VOID *storage_instance, ULONG lun, ULONG number_blocks,
ULONG lba, ULONG *media_status)
{
UINT status = UX_SUCCESS;
/* USER CODE BEGIN USBD_STORAGE_Flush */
if (fx_media_cache_invalidate(sdioDisk) != FX_SUCCESS || fx_media_flush(sdioDisk) != FX_SUCCESS) {
status = UX_ERROR;
}
/* USER CODE END USBD_STORAGE_Flush */
return status;
}
2. When I use local FileX to create a new file, and call function fx_media_flush, the Host PC-Windows can't see th new file until the usb reconnect. Seem windows explorer cache not fresh.
3. Based on point 2, I want to implement function USBD_STORAGE_Status, when some changes happend in local, return a UX_ERROR and media_status with Sense Key = UNIT ATTENTION (0x06), ASC/ASCQ = NOT READY TO READY CHANGE, MEDIA MAY HAVE CHANGED (0x28, 0x00). The purpose is let host reread the U-DISK's FAT32 table.
UINT USBD_STORAGE_Status(VOID *storage_instance, ULONG lun, ULONG media_id,
ULONG *media_status)
{
UINT status = UX_SUCCESS;
/* USER CODE BEGIN USBD_STORAGE_Status */
UX_PARAMETER_NOT_USED(storage_instance);
UX_PARAMETER_NOT_USED(lun);
UX_PARAMETER_NOT_USED(media_id);
UX_PARAMETER_NOT_USED(media_status);
/* USER CODE END USBD_STORAGE_Status */
return status;
}
I want to know if this method is feasible? THANK YOU!