The Micro SD Card Module allows Arduino to read and write data to a microSD card, making it ideal for data logging, storing sensor readings, or managing files in Arduino projects. This tutorial will guide you through connecting and using the Micro SD Card Module with Arduino.
What You Will Need
- Micro SD Card Module
- Arduino Board (e.g., Uno, Mega, Nano)
- MicroSD Card (formatted to FAT32)
- Breadboard and Jumper Wires
- A computer with the Arduino IDE installed
Step 1: Understanding the Micro SD Card Module
The module uses the SPI protocol to communicate with Arduino. It has onboard voltage regulators, allowing it to work with both 5V and 3.3V microcontrollers.
Micro SD Card Module Pinout
| Pin | Function |
|---|---|
| VCC | Power Supply (3.3V/5V) |
| GND | Ground |
| MISO | SPI Data Output |
| MOSI | SPI Data Input |
| SCK | SPI Clock |
| CS | Chip Select |
Step 2: Wiring the Micro SD Card Module to Arduino
Here’s how to connect the Micro SD Card Module to an Arduino Uno:
| Micro SD Pin | Arduino Pin |
|---|---|
| VCC | 5V |
| GND | GND |
| MISO | Pin 12 |
| MOSI | Pin 11 |
| SCK | Pin 13 |
| CS | Pin 10 |
Note: If you’re using a different Arduino board, ensure the SPI pins match your board’s pinout.
Step 3: Install the Required Library
The SD library is built into the Arduino IDE and simplifies reading from and writing to SD cards.
Steps to Verify Library Installation:
- Open the Arduino IDE.
- Go to Sketch > Include Library.
- Ensure the "SD" library is listed. If not, install it from the Library Manager.
Step 4: Upload the Code
Here is an example sketch to write and read data from the SD card:
Example Code: Writing and Reading Data
#include <SPI.h>
#include <SD.h>
#define CS_PIN 10 // Chip Select pin for the SD card module
File myFile;
void setup() {
Serial.begin(9600);
while (!Serial);
Serial.println("Initializing SD card...");
if (!SD.begin(CS_PIN)) {
Serial.println("SD card initialization failed!");
return;
}
Serial.println("SD card initialized.");
// Write to the SD card
myFile = SD.open("test.txt", FILE_WRITE);
if (myFile) {
Serial.println("Writing to test.txt...");
myFile.println("Hello, SD card!");
myFile.close();
Serial.println("Write complete.");
} else {
Serial.println("Error opening test.txt for writing.");
}
// Read from the SD card
myFile = SD.open("test.txt");
if (myFile) {
Serial.println("Reading from test.txt...");
while (myFile.available()) {
Serial.write(myFile.read());
}
myFile.close();
} else {
Serial.println("Error opening test.txt for reading.");
}
}
void loop() {
// Nothing to do here
}
Step 5: Test the Setup
- Connect the Arduino to your computer via USB.
- Open the Arduino IDE and select the correct Board and Port under the Tools menu.
- Upload the code to the Arduino by clicking Upload.
- Open the Serial Monitor (Tools > Serial Monitor) and set the baud rate to
9600. - Observe messages about the SD card initialization, data writing, and data reading in the Serial Monitor.
Optional: Formatting the SD Card
Ensure your SD card is formatted to FAT16 or FAT32 before use. Use your operating system’s formatting tool or software like SD Card Formatter.
Applications of the Micro SD Card Module
- Data logging (e.g., temperature, humidity, or motion sensors)
- Storing configuration files for IoT projects
- Saving images or audio for multimedia projects
- Building file-based storage systems
Troubleshooting
- SD card initialization failed: Ensure proper wiring and check that the SD card is formatted correctly.
- Error opening files: Verify the file name and ensure it does not exceed 8 characters (plus a 3-character extension).
- Unstable operation: Use a stable 5V power supply and avoid long jumper wires.
Conclusion
You’ve successfully interfaced the Micro SD Card Module with Arduino, enabling data storage and retrieval for your projects. This versatile module is essential for creating data loggers, multimedia devices, or file-based systems. Experiment further by reading and writing larger files or integrating the SD card module with sensors and displays!
