The S-Play references the first partition of an SD card only.
For the best experience, ENTTEC recommends removing all content from your SD card and creating one large, empty partition before inserting it into your S-Play.
The SD card should be formatted as FAT or FAT32.
Test the SD card can be seen by the S-Play by navigating to its backup page.
For more in-depth information, refer to the S-Play product guide.