1 | /*
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2 | SD card file dump
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3 |
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4 | This example shows how to read a file from the SD card using the
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5 | SD library and send it over the serial port.
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6 |
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7 | The circuit:
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8 | * SD card attached to SPI bus as follows:
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9 | ** MOSI - pin 11
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10 | ** MISO - pin 12
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11 | ** CLK - pin 13
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12 | ** CS - pin 4
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13 |
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14 | created 22 December 2010
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15 | by Limor Fried
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16 | modified 9 Apr 2012
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17 | by Tom Igoe
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18 |
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19 | This example code is in the public domain.
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20 |
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21 | */
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22 |
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23 | #include <SPI.h>
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24 | #include <SD.h>
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25 |
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26 | // On the Ethernet Shield, CS is pin 4. Note that even if it's not
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27 | // used as the CS pin, the hardware CS pin (10 on most Arduino boards,
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28 | // 53 on the Mega) must be left as an output or the SD library
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29 | // functions will not work.
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30 | const int chipSelect = 4;
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31 |
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32 | void setup()
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33 | {
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34 | // Open serial communications and wait for port to open:
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35 | Serial.begin(9600);
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36 | while (!Serial) {
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37 | ; // wait for serial port to connect. Needed for Leonardo only
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38 | }
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39 |
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40 |
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41 | Serial.print("Initializing SD card...");
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42 | // make sure that the default chip select pin is set to
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43 | // output, even if you don't use it:
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44 | // pinMode(10, OUTPUT);
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45 |
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46 | // see if the card is present and can be initialized:
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47 | if (!SD.begin(chipSelect)) {
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48 | Serial.println("Card failed, or not present");
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49 | // don't do anything more:
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50 | return;
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51 | }
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52 | Serial.println("card initialized.");
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53 |
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54 | // open the file. note that only one file can be open at a time,
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55 | // so you have to close this one before opening another.
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56 | File dataFile = SD.open("datalog.txt");
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57 |
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58 | // if the file is available, write to it:
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59 | if (dataFile) {
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60 | while (dataFile.available()) {
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61 | Serial.write(dataFile.read());
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62 | }
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63 | dataFile.close();
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64 | }
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65 | // if the file isn't open, pop up an error:
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66 | else {
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67 | Serial.println("error opening datalog.txt");
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68 | }
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69 | }
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70 |
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71 | void loop()
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72 | {
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73 | }
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74 |
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