6.43. MSC Host

6.43.1. Overview

This example project shows USB MSC Host

6.43.2. Board Setting

  • Connect a USB port on PC to the PWR DEBUG port on the development board with a USB Type-C cable

  • Connect a USB port on the development board USB0 to a USB flash disk(Attention: The Format Type support FAT, FAT32 or exFAT) with a USB Type-C convert Type-A cable

    UDisk_Format

6.43.3. Software Setting

  • In the CMakeLists.txt file, if sdk_compile_definitions(-DFATFS_ONLY_NONCACHEABLE_BUF=1) is commented, FATFS supports data transfer by using cacheable buffer. If sdk_compile_definitions(-DFATFS_ONLY_NONCACHEABLE_BUF=1) is uncommented, FATFS only supports data transfer by using noncacheable buffer.

  • When sdk_compile_definitions(-DFATFS_ONLY_NONCACHEABLE_BUF=1) is commented, it is recommended to align cache line size for the buffer address, otherwise it will affect transmission performance.

6.43.4. Running the example

  • Download the program to the development board to run, and use the serial port debugging assistant to view the output log

  • First, a “cherryusb _msc_test.txt” file will be created in the USB flash drive, and the string “cherryusb fatfs demo…” will be written into the file, with a total of 100 lines or 2500 bytes; Then read out the data of the file, with a total length of 2500.

  • Secondly, it will scan the directories and files under the root directory of the USB drive and print out the directory name and file name.

6.43.5. Example of output log

  • When the USB port0 of the development board is connected with a USB flash disk, the serial port debugging assistant will display the following data:

FATFS cherryusb mount succeeded!
test fatfs write
write success, write len：2500
test fatfs read
read success, read len：2500

Direcotry Path: /
Folder Name: LOST.DIR
Folder Name: DCIM
Folder Name: MIUI
Folder Name: Android
Folder Name: tencent
File   Name: USBHost.txt
File   Name: cherryusb_msc_test.txt