diff options
| author | Jesse Morgan <jesse@jesterpm.net> | 2011-10-20 22:16:19 -0700 |
|---|---|---|
| committer | Jesse Morgan <jesse@jesterpm.net> | 2011-10-20 22:16:19 -0700 |
| commit | fc944ff979dbbd49a57722fe2d1d2acf47312eb4 (patch) | |
| tree | 38cc3a5c5c8f24f55068fc4ffa73d018169fc2df /libraries/SD/examples/ReadWrite/ReadWrite.pde | |
Inital commit... halfway through the project
Diffstat (limited to 'libraries/SD/examples/ReadWrite/ReadWrite.pde')
| -rw-r--r-- | libraries/SD/examples/ReadWrite/ReadWrite.pde | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/libraries/SD/examples/ReadWrite/ReadWrite.pde b/libraries/SD/examples/ReadWrite/ReadWrite.pde new file mode 100644 index 0000000..fcdd428 --- /dev/null +++ b/libraries/SD/examples/ReadWrite/ReadWrite.pde @@ -0,0 +1,79 @@ +/*
+ SD card read/write
+
+ This example shows how to read and write data to and from 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
+ updated 2 Dec 2010
+ by Tom Igoe
+
+ This example code is in the public domain.
+
+ */
+
+#include <SD.h>
+
+File myFile;
+
+void setup()
+{
+ Serial.begin(9600);
+ 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) must be left as an output
+ // or the SD library functions will not work.
+ pinMode(10, OUTPUT);
+
+ if (!SD.begin(4)) {
+ Serial.println("initialization failed!");
+ return;
+ }
+ Serial.println("initialization done.");
+
+ // open the file. note that only one file can be open at a time,
+ // so you have to close this one before opening another.
+ myFile = SD.open("test.txt", FILE_WRITE);
+
+ // if the file opened okay, write to it:
+ if (myFile) {
+ Serial.print("Writing to test.txt...");
+ myFile.println("testing 1, 2, 3.");
+ // close the file:
+ myFile.close();
+ Serial.println("done.");
+ } else {
+ // if the file didn't open, print an error:
+ Serial.println("error opening test.txt");
+ }
+
+ // re-open the file for reading:
+ myFile = SD.open("test.txt");
+ if (myFile) {
+ Serial.println("test.txt:");
+
+ // read from the file until there's nothing else in it:
+ while (myFile.available()) {
+ Serial.write(myFile.read());
+ }
+ // close the file:
+ myFile.close();
+ } else {
+ // if the file didn't open, print an error:
+ Serial.println("error opening test.txt");
+ }
+}
+
+void loop()
+{
+ // nothing happens after setup
+}
+
+
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