SDfilesystem example for WIZwiki-W7500

Dependencies:   SDFileSystem mbed

Fork of SDFileSystem_HelloWorld by mbed official


SD Cards are widely used by loads of devices for storage; phones, mp3 players, pc's etc. That means they are a very cheap option for storing large amounts of non-volatile data (i.e. the data is not lost when the power is removed). They should be ideal for data logging and storing audio/images.

WIZwiki-W7500 have a SD card slot that can operate in its SPI interface.

This library is to allow SD card File System on WIZwiki-W7500 and updating MP3 files from server to SD card via FTP protocol.

To implement this function, you need a Platform board and SD card. Below are what we used.

  • WIZwiki-W7500 from WIZnet (Platform board and Ethernet I/F board)
  • SD card

Hardware Configuration

WIZwiki-W7500 Pin map

pin map

SPI1 for SD Card
SPI1 on WIZwiki-W7100 is for reading from or writing to SD card and pins for SPI1 are PB_0, PB_1, PB_2 and PB_3.


SPI Initialization


SDFileSystem sd(PB_3, PB_2, PB_1, PB_0, "sd"); // the pinout on the mbed Cool Components workshop board

Make Directory and Open a Text File


   // Make Directory
    mkdir("/sd/mydir", 0777);
  // File Open for writing
    FILE *fp = fopen("/sd/mydir/sdtest.txt", "w");
    if(fp == NULL) {
        error("Could not open file for write\n");

Write Text into File


    fprintf(fp, "Hello fun SD Card World!");


This example can access SD File system and write Message into SD File system