/* SD card basic file example This example shows how to create and destroy an SD card file The circuit: * SD card attached to SPI bus as follows: ** MOSI - pin 11 ** MISO - pin 12 ** CLK - pin 13 ** CS - pin 4 created Nov 2010 by David A. Mellis modified 9 Apr 2012 by Tom Igoe This example code is in the public domain. */ #include #include File myFile; void setup() { // Open serial communications and wait for port to open: Serial.begin(9600); while (!Serial) { ; // wait for serial port to connect. Needed for Leonardo only } Serial.print("Initializing SD card..."); // On the Ethernet Shield, CS is pin 4. It's set as an output by default. // Note that even if it's not used as the CS pin, the hardware SS pin // (10 on most Arduino boards, 53 on the Mega, 14 on the Leonardo) must be left as an output // or the SD library functions will not work. if (!SD.begin(4)) { Serial.println("initialization failed!"); return; } Serial.println("initialization done."); if (SD.exists("example.txt")) { Serial.println("example.txt exists."); } else { Serial.println("example.txt doesn't exist."); } // open a new file and immediately close it: Serial.println("Creating example.txt..."); myFile = SD.open("example.txt", FILE_WRITE); myFile.close(); // Check to see if the file exists: if (SD.exists("example.txt")) { Serial.println("example.txt exists."); } else { Serial.println("example.txt doesn't exist."); } // delete the file: Serial.println("Removing example.txt..."); SD.remove("example.txt"); if (SD.exists("example.txt")) { Serial.println("example.txt exists."); } else { Serial.println("example.txt doesn't exist."); } } void loop() { // nothing happens after setup finishes. }