SD Card Writing problem

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1

I have some issues writing to a csv file in an SD Card.
I wrote and tested my code with an old SD card module and once I changed the reader to the basic SD Card Module SKU: 018-DB-SDCARD it stopped working. I am using an Arduino Uno, and even running sample code SD - Card Info fails.
I wonder if I am missing a step or if there is any extra documentation on such module.

2

Hi Susana,

Thanks for your message - we’ll get back to you tomorrow morning with a way forward (just snagged us at the end of the day)

3

Hey Susana,
Just taking a look at this module alongside your post. I might need a little additional information on your issue so that I can help you out. Are you getting a card read failed on the SD.Begin function in your code?

4

Hi Susana, was your previous card module using SPI as per the Arduino SDcard library?
Might need to take a look at your code/hardware setup

5

Yes , it uses SPI. Attached Image of the other SD card module. When I run the example code “Card Info” and it is the first time that I run the code since placing the card it runs, but it doesn’t after.

In my main code, which is a data logger. Sometimes the card initialises (sometimes it doesn’t) but I never get to write on it (See save data code excerpt). So it seems again that it can’t read it.

  rtc.begin();

  // CSpin is on pin 4, tried with 10 as well but no luck
  if (!SD.begin(CSpin)) {
    Serial.println("Card failed, or not present");
    // don't do anything more:
    while(1);
  }
  Serial.println("card initialized.");
}

------------------------------------------------
// Save data
 if (SD.exists("data.csv")) { 
//     now append new data file
    sensorData = SD.open("data.csv", FILE_WRITE);
    if (sensorData) {
      sensorData.println(dataString);
      delay(10);
      sensorData.close(); // close the file
    }
  }
  else {
    Serial.println("Error writing to file !");
  }
}
6

Hmm sounds interesting. When you say it doesn’t run, or doesn’t initialise, what exactly is happening when it doesn’t work, does it just print nothing, do you get an error?

7

Try checking the SD card format (FAT32 is what you want) and that the SD card is MBR. It could be worth reducing the SPI bus speed to half.