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75 lines
1.7 KiB
C++
75 lines
1.7 KiB
C++
/*
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SD card file dump
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This example shows how to read a file from the SD card using the
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SD library and send it over the serial port.
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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 22 December 2010
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by Limor Fried
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modified 9 Apr 2012
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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 <SPI.h>
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#include <SD.h>
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// On the Ethernet Shield, CS is pin 4. Note that even if it's not
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// used as the CS pin, the hardware CS pin (10 on most Arduino boards,
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// 53 on the Mega) must be left as an output or the SD library
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// functions will not work.
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const int chipSelect = 4;
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void setup()
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{
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// Open serial communications and wait for port to open:
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Serial.begin(9600);
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while (!Serial) {
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; // wait for serial port to connect. Needed for Leonardo only
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}
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Serial.print("Initializing SD card...");
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// make sure that the default chip select pin is set to
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// output, even if you don't use it:
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pinMode(10, OUTPUT);
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// see if the card is present and can be initialized:
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if (!SD.begin(chipSelect)) {
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Serial.println("Card failed, or not present");
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// don't do anything more:
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return;
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}
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Serial.println("card initialized.");
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// open the file. note that only one file can be open at a time,
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// so you have to close this one before opening another.
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File dataFile = SD.open("datalog.txt");
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// if the file is available, write to it:
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if (dataFile) {
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while (dataFile.available()) {
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Serial.write(dataFile.read());
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}
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dataFile.close();
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}
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// if the file isn't open, pop up an error:
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else {
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Serial.println("error opening datalog.txt");
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}
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}
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void loop()
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{
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}
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