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USB Disk Driver

The USB disk driver requires RTUSB-32 and supports all USB disks which adhere to the USB Mass Storage Device Specification, class code 8, subclass 2 (MMC-2), 4 (UFI), 5 (FDD), or 6 (SCSI), protocols 0 (Control/Bulk/Interrupt), 1 (Control/Bulk/Interrupt, no Interrupt status), or 50h (Bulk only). Any number of devices with up to 2³² sectors each are supported.

Before the USB disk driver can be used, the RTUSB-32 attachment/detachment callback USBDisk must be registered using RTUSB-32 API function RTURegisterCallback.

RTFDevice.DeviceType

RTFDevice.DeviceType must be set to RTF_DEVICE_FDISK for USB hard disks, flash disks, memory sticks, etc. For USB floppy disk drives, it must be RTF_DEVICE_FLOPPY.

RTFDevice.DeviceNumber

This field is the LUN (Logical disk Unit) on the USB device to access. Most USB mass storage devices contain just one disk with a LUN of 0, so this value should usually be 0. However, card readers or similar devices may implement several LUNs. To use a multi-LUN device with n LUNs, consecutive device list entries are required with device numbers starting from 0 up to n-1. The device list entries must be ordered by ascending DeviceNumbers. The respective RTFDrvUSBData of each entry must be contiguous in memory, allocated in an array.

RTFDevice.DeviceFlags

The USB disk driver does not define any device dependent device flags. Flag RTF_DEVICE_NEW_LOCK is supported and recommended for each USB disk with device number 0. All other device independent flags documented in section Device List are supported.

RTFDevice.Driver

This field must point to RTFDrvUSB.

RTFDevice.DriverData

The USB disk driver requires a pointer to a structure of type RTFDrvUSBData. The structure should be left uninitialized or initialized to 0.

Example:

static RTFDrvFLPYData FLPYDriveA       = {0}; 
static RTFDrvUSBData  USBFloppy        = {0}; 
static RTFDrvIDEData  IDEDriveC        = {0}; 
static RTFDrvUSBData  USBDisk1         = {0}; 
static RTFDrvUSBData  USBCardReader[4] = {0}; 

RTFDevice RTFDeviceList[] = { 
  { RTF_DEVICE_FLOPPY, 0, 0,                   &RTFDrvFloppy, &FLPYDriveA}, 

  { RTF_DEVICE_FLOPPY, 0, 0,                   &RTFDrvUSB,    &USBFloppy}, 

  { RTF_DEVICE_FDISK , 0, 0,                   &RTFDrvIDE,    &IDEDriveC }, 

  { RTF_DEVICE_FDISK , 0, RTF_DEVICE_NEW_LOCK, &RTFDrvUSB,    &USBDisk1}, 

  { RTF_DEVICE_FDISK , 0, RTF_DEVICE_NEW_LOCK, &RTFDrvUSB,    USBCardReader + 0}, 
  { RTF_DEVICE_FDISK , 1, 0,                   &RTFDrvUSB,    USBCardReader + 1}, 
  { RTF_DEVICE_FDISK , 2, 0,                   &RTFDrvUSB,    USBCardReader + 2}, 
  { RTF_DEVICE_FDISK , 3, 0,                   &RTFDrvUSB,    USBCardReader + 3}, 
  { 0 } 
};

The device list above supports a legacy floppy disk, a USB floppy, an IDE disk on the primary/master channel, one USB disk, and a USB card reader with up to 4 card slots.

Device Drivers

MTD Drivers RTFMtdCFI2_x

NULL Device Driver