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79 lines
1.6 KiB
Plaintext
79 lines
1.6 KiB
Plaintext
/*
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SD card basic file example
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This example shows how to create and destroy an SD card file
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The circuit:
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* SD card attached to SPI bus as follows:
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** MOSI - pin 11
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** MISO - pin 12
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** CLK - pin 13
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** CS - pin 4
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created Nov 2010
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by David A. Mellis
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updated 2 Dec 2010
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by Tom Igoe
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This example code is in the public domain.
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*/
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#include <SD.h>
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File myFile;
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void setup()
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{
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Serial.begin(9600);
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Serial.print("Initializing SD card...");
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// On the Ethernet Shield, CS is pin 4. It's set as an output by default.
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// Note that even if it's not used as the CS pin, the hardware SS pin
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// (10 on most Arduino boards, 53 on the Mega) must be left as an output
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// or the SD library functions will not work.
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pinMode(10, OUTPUT);
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if (!SD.begin(4)) {
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Serial.println("initialization failed!");
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return;
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}
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Serial.println("initialization done.");
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if (SD.exists("example.txt")) {
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Serial.println("example.txt exists.");
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}
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else {
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Serial.println("example.txt doesn't exist.");
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}
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// open a new file and immediately close it:
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Serial.println("Creating example.txt...");
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myFile = SD.open("example.txt", FILE_WRITE);
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myFile.close();
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// Check to see if the file exists:
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if (SD.exists("example.txt")) {
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Serial.println("example.txt exists.");
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}
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else {
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Serial.println("example.txt doesn't exist.");
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}
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// delete the file:
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Serial.println("Removing example.txt...");
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SD.remove("example.txt");
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if (SD.exists("example.txt")){
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Serial.println("example.txt exists.");
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}
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else {
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Serial.println("example.txt doesn't exist.");
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}
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}
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void loop()
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{
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// nothing happens after setup finishes.
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}
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