1.4 FAT Filesystem using SDMMC Media

Description

File System Operations on the SD Card:

Application opens a file named FILE_TOO_LONG_NAME_EXAMPLE_123.JPG in the root directory of the SD card and reads its content into memory
- The image file could be any arbitrary JPEG (image) file chosen by the user and then renamed to FILE_TOO_LONG_NAME_EXAMPLE_123.JPG
Application creates directory named Dir1 in the root directory
Application creates a new file named FILE_TOO_LONG_NAME_EXAMPLE_123.JPG inside Dir1
Application copies the content from step 1 into this newly created file

The reason for choosing a JPEG file for test purposes is that the duplicate file, Dir1/FILE_TOO_LONG_NAME_EXAMPLE_123.JPG created by the demonstration could be easily verified for correctness. If the new file inside Dir1 opens for viewing on the computer and matches to original image, the test is deemed to have passed. Otherwise, if the file does not open (i.e., is corrupted), the test will be considered to have failed.

Note: Since the application creates a directory named Dir1, it is important that the a folder with the same name does not exist on the SD card. If a directory named Dir1 is already present on the SD card, the application will fail.

Downloading and Building the Application

To clone or download this application from Github, go to the main page of this repository and then click Clone button to clone this repository or download as zip file. This content can also be downloaded using content manager by following these instructions.

Path of the application within the repository is apps/fs/sdmmc_fat/firmware.

To build the application, refer to the following table and open the project using its IDE.


Project Name	Description
sam_9x60_curiosity.X	MPLABX project for SAM9X60-Curiosity board
sam_9x60_curiosity_freertos.X	MPLABX project for SAM9X60-Curiosity board

Setting Up AT91Bootstrap loader

To load the application binary onto the target device, we need to use at91bootstrap loader. Refer to the at91bootstrap loader documentation for details on how to use it to bootstrap the application binaries.

Setting Up the Hardware

The following table shows the target hardware for the application projects.


Project Name	Description
sam_9x60_curiosity.X sam_9x60_curiosity_freertos.X	SAM9X60-Curiosity board

Setting Up SAM9X60-Curiosity Board

Insert the SD card into SDMMC0 (J3) slot on the board (SD Card with FAT32 file system and FILE_TOO_LONG_NAME_EXAMPLE_123.JPG file)
Connect the USB port J1 on board to the computer using a micro USB cable (to power the board)
Connect the JTAG J12 on board to the computer using a JTAG based debugger

Running the Application

Build and program the application using its IDE
The LED is turned ON if there was no error during creating the directory and copying the file into it

Refer to the following table for LED name:


Board	LED Name
SAM9X60-Curiosity board	RGB_LED (Green)