I am experimenting with the ReadWrite example provided with the SD card library. Code copied below.
I am getting odd results in Ubuntu. Sometimes I get extra directories and files created on the card (screen shot attached). The file names are like the text for the data file. This appears to happen at random?
When I double click to open the file in Ubuntu I get an error, suggesting that I am using the wrong character encoding? Is this a typical result and is it a problem? I can see the data I want, but also extra characters.
I want to be able to log to the SD card over weeks and then use the files as spreadsheet entires. At the moment I am testing the hardware and am not confident with these odd results. I have a SD card including on the Ethernet shield I am using.
/*
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
}
