Create USB Host MSC Applications

Create USB Host MSC Applications shows how to create a USB Host application that supports the mass storage class using the RL-USB Library.

Include into the project and configure the following RL-USB Host Source Files:

1. The USB library that matches the device core:
   USB_CM1.lib - for Cortex-M1 devices.
   USB_CM3.lib - for Cortex-M3 devices.
   USB_ARM_L.lib - for ARM7 or ARM9 devices.
2. The FlashFile library that matches the device core:
   FS_CM3.lib - for Cortex-M3 devices.
   FS_ARM_L.lib - for ARM7 or ARM9 devices.
3. usbh_ohci_device family.c - to configure the device hardware layer for devices with OHCI host controllers or usbh_device family.c - to configure the device hardware layer for devices with Custom host controllers.
4. usb_config.c - to configure the USB system.
5. File_Config.c - to configure the USB Flash Drive.
6. fs_usbh_msc.c - to adapt the code to the application needs.
7. main file.c - to initialize the USB Host from main().

   ..
   usbh_init(0);                                            // initialize USB Host Controller 0
   while(1) {
     ..
     usbh_engine(0);                                        // check for new devices
     ..
   }
   

Several µVision USB Host MSD projects can be used as a template for creating new USB Host MSD applications. The files can be edited directly or using the µVision Configuration Wizard.

1. Copy all files from any folder \ARM\Boards\Vendor\Board\RL\USB\Host\MSD_File to a new folder and open the *.uvproj project with µVision.
2. Open the file usb_config.c and enable USB Host x.

For USB Host devices that support OHCI:

3. Select the option OHCI in Controller Interface.
   
4. In the Class Configuration section, set Mass Storage Device Class (MSC).
5. Open the file usbh_ohci_device family.c and set the USB Host OHCI Settings.
   

For USB Host devices that support a Custom USB Host Controller:

3. Select the option Custom in Controller Interface.
   
4. In the Class Configuration section, set Mass Storage Device Class (MSC).

Continue configuring the USB Flash Drive. Option details are explained in USB Flash Drive.

1. Open the file File_Config.c, enable the option USB Flash Drive.
   
2. Define the File System Cache size.
3. Enable Default Drive [U0:].

Finally, modify the file fs_usbh_msc.c to suite the application requirements.

Note

• The configuration options are explained in RL-USB Host Configuration.