Hi, guys.
I'm trying to run the examples of SD library but it is not working. I'm able to read the card (CardInfo example), and to create a new file when I run examples like Datalogger.
I'm using an Arduino MEGA 2560 and a Sandisk SD2 1GB card with a module identical to the one in the image
The pins are connected as follows:
MISO - 50;
SCK - 52;
MOSI - 51;
CS - 53.
The code:
/*
SD card datalogger
This example shows how to log data from three analog sensors
to an SD card using the SD library.
The circuit:
* SD card attached to SPI bus as follows:
** UNO: MOSI - pin 11, MISO - pin 12, CLK - pin 13, CS - pin 4 (CS pin can be changed)
and pin #10 (SS) must be an output
** Mega: MOSI - pin 51, MISO - pin 50, CLK - pin 52, CS - pin 4 (CS pin can be changed)
and pin #52 (SS) must be an output
** Leonardo: Connect to hardware SPI via the ICSP header
Pin 4 used here for consistency with other Arduino examples
created 24 Nov 2010
modified 9 Apr 2012 by Tom Igoe
This example code is in the public domain.
*/
#include <SPI.h>
#include <SD.h>
// On the Ethernet Shield, CS is pin 4. Note that even if it's not
// used as the CS pin, the hardware CS pin (10 on most Arduino boards,
// 53 on the Mega) must be left as an output or the SD library
// functions will not work.
const int chipSelect = 53;
File dataFile;
void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
Serial.print("Initializing SD card...");
// make sure that the default chip select pin is set to
// output, even if you don't use it:
pinMode(SS, OUTPUT);
// see if the card is present and can be initialized:
if (!SD.begin(chipSelect)) {
Serial.println("Card failed, or not present");
// don't do anything more:
while (1) ;
}
Serial.println("card initialized.");
// Open up the file we're going to log to!
dataFile = SD.open("datalog.txt", FILE_WRITE);
if (! dataFile) {
Serial.println("error opening datalog.txt");
// Wait forever since we cant write data
while (1) ;
}
}
void loop()
{
// make a string for assembling the data to log:
String dataString = "";
// read three sensors and append to the string:
for (int analogPin = 0; analogPin < 3; analogPin++) {
int sensor = analogRead(analogPin);
dataString += String(sensor);
if (analogPin < 2) {
dataString += ",";
}
}
dataFile.println(dataString);
// print to the serial port too:
Serial.println(dataString);
// The following line will 'save' the file to the SD card after every
// line of data - this will use more power and slow down how much data
// you can read but it's safer!
// If you want to speed up the system, remove the call to flush() and it
// will save the file only every 512 bytes - every time a sector on the
// SD card is filled with data.
dataFile.flush();
// Take 1 measurement every 500 milliseconds
delay(500);
}
The Serial Monitor shows the strings, and the file named datalog (or other name) is created if not existing, but nothing is recorded to that file.
I even tryed to use another pin instead of 53 (also changing that value in the code) but the same thing happened. What's going on?
Thanks!
