SD card module wiring in Arduino - Step-by-Step Execution

Concept Flow - SD card module wiring

Power Supply

↓

SD Card Module VCC

↓

SD Card Module GND

↓

SPI Communication Pins

↓

MOSI

↓

MISO

↓

SCK

↓

CS

↓

Arduino SPI Interface

↓

SD Card Module Ready for Data Transfer

This flow shows how to connect the SD card module pins to the Arduino pins for power and SPI communication.

Execution Sample

Arduino

// SD card wiring connections
const int chipSelect = 10;
// Connect VCC to 5V or 3.3V
// Connect GND to GND
// Connect MOSI to pin 11
// Connect MISO to pin 12
// Connect SCK to pin 13
// Connect CS to pin 10

This code comments show the wiring connections needed for the SD card module to communicate with Arduino using SPI.

Execution Table

Step	Pin on SD Module	Connected Arduino Pin	Purpose	Notes
1	VCC	5V or 3.3V	Power supply	Check module voltage requirements
2	GND	GND	Ground connection	Common ground with Arduino
3	MOSI	Pin 11	Master Out Slave In	Data from Arduino to SD
4	MISO	Pin 12	Master In Slave Out	Data from SD to Arduino
5	SCK	Pin 13	Clock signal	Synchronizes data transfer
6	CS	Pin 10	Chip Select	Selects SD card for communication
7	-	-	-	All connections complete, ready for SPI communication

💡 All required pins connected correctly, SD card module ready for use.

Variable Tracker

Pin	Initial	Connected To
VCC	Not connected	5V or 3.3V
GND	Not connected	GND
MOSI	Not connected	Pin 11
MISO	Not connected	Pin 12
SCK	Not connected	Pin 13
CS	Not connected	Pin 10

Key Moments - 3 Insights

Why do we connect the CS pin to pin 10 on Arduino?

Pin 10 is the default Chip Select pin for SPI on Arduino; it tells the SD card module when to listen or ignore communication, as shown in execution_table step 6.

Can we connect VCC to 5V or 3.3V? Which one should we choose?

It depends on your SD card module voltage rating. Some modules work with 3.3V only, others accept 5V. Check the module specs before wiring, as noted in execution_table step 1.

What happens if MOSI and MISO pins are swapped?

Data will not transfer correctly because MOSI sends data from Arduino to SD, and MISO sends data back. Swapping them breaks communication, so follow steps 3 and 4 carefully.

Visual Quiz - 3 Questions

Look at the execution_table, which Arduino pin is used for the clock signal (SCK)?

A Pin 12

B Pin 13

C Pin 11

D Pin 10

💡 Hint

Check the row where Pin on SD Module is SCK in the execution_table.

At which step in the execution_table do we connect the ground (GND) pin?

A Step 1

B Step 5

C Step 2

D Step 6

💡 Hint

Look for the row where Pin on SD Module is GND.

If you connect CS to pin 9 instead of pin 10, what changes in the wiring?

A You must update the chipSelect variable in code to 9

B You must connect MOSI to pin 9

C No change, pin 9 works the same as pin 10

D You must connect SCK to pin 9

💡 Hint

Refer to the execution_sample code where chipSelect is set to pin 10.

Concept Snapshot

SD card module wiring for Arduino:
- Connect VCC to 3.3V or 5V (check module specs)
- Connect GND to Arduino GND
- Connect SPI pins: MOSI->11, MISO->12, SCK->13
- Connect CS (Chip Select) to pin 10
- Use SPI interface for communication

Full Transcript

This visual execution shows how to wire an SD card module to an Arduino board. First, connect the power pins: VCC to 3.3V or 5V depending on the module, and GND to ground. Then connect the SPI communication pins: MOSI to pin 11, MISO to pin 12, SCK to pin 13, and CS (chip select) to pin 10. These connections allow the Arduino to communicate with the SD card using the SPI protocol. The wiring must be correct for the SD card to work. The chipSelect pin in code must match the physical CS pin connection. This setup prepares the SD card module for data transfer.