1.5 FAT File System using SD Card Media

This application shows an example of using the MPLAB Harmony File System to access and modify the contents of a SD card using the SDSPI driver and the SPI PLIB.

Description

File System Operations on the SD Card:

The application opens a file named FILE_TOO_LONG_NAME_EXAMPLE_123.JPG on the SD card
Reads the content of the file and creates a directory named Dir1
Inside the directory, writes the copied content into another file Dir1/FILE_TOO_LONG_NAME_EXAMPLE_123.JPG

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.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.

File system layer uses:

SDSPI Driver to communicate to SD Card over SPI interface.

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/sdspi_fat/firmware.

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


Project Name	Description
sam_c21n_xpro.X	MPLABX project for SAMC21N Xplained Pro Evaluation Kit

Setting Up the Hardware

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


Project Name	Description
sam_c21n_xpro.X	SAMC21N Xplained Pro Evaluation Kit

Setting Up SAMC21N Xplained Pro Evaluation Kit

To run the demo, the following additional hardware are required:
- One IO1 Xplained Pro Extension Kit
- One micro-sd card
Connect IO1 Xplained Pro Extension Kit to the EXT1 header
Copy a JPEG file in the SD Card with name FILE_TOO_LONG_NAME_EXAMPLE_123.JPG
Insert the micro-SD Card in the micro-SD Card slot of the IO1 Xplained Pro Extension Kit
Connect the Debug USB port on the board to the computer using a micro USB cable

Running the Application

Build and program the application using its IDE
Press Switch to start the file operations
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 Switch and LED names:
Board Switch Name LED Name
SAMC21N Xplained Pro Evaluation Kit SW0 LED0
If LED is ON, Insert the SD Card on to your host PC
SD Card should have the file Dir1/FILE_TOO_LONG_NAME_EXAMPLE_123.JPG and should match the original image