External storage is one of those features that instantly upgrades a microcontroller project from demo to useful. Whether you’re logging sensor data, saving configuration files, or storing timestamps, an SD card gives you gigabytes of non-volatile storage with very little effort.
In this guide, we’ll build a Raspberry Pi Pico sd card Module, and go one step further by making it interactive through the Serial Monitor. You’ll be able to create files, write custom text, read data back, and delete files in real time - perfect for understanding how embedded systems handle external storage.
This project is beginner-friendly and a great foundation before moving on to more advan…
External storage is one of those features that instantly upgrades a microcontroller project from demo to useful. Whether you’re logging sensor data, saving configuration files, or storing timestamps, an SD card gives you gigabytes of non-volatile storage with very little effort.
In this guide, we’ll build a Raspberry Pi Pico sd card Module, and go one step further by making it interactive through the Serial Monitor. You’ll be able to create files, write custom text, read data back, and delete files in real time - perfect for understanding how embedded systems handle external storage.
This project is beginner-friendly and a great foundation before moving on to more advanced data-logging builds.
Components Required
| Component | Quantity |
|---|---|
| Raspberry Pi Pico | 1 |
| SD Card Module (SPI, 3.3V) | 1 |
| microSD Card (FAT32) | 1 |
| Breadboard & Jumper Wires | As needed |
| USB Cable | 1 |
Wiring: Raspberry Pi Pico ↔ SD Card (SPI0)
| Pico Pin | SD Pin |
|---|---|
| 3V3 | VCC |
| GND | GND |
| GP19 | MOSI |
| GP16 | MISO |
| GP18 | SCK |
| GP17 | CS |
This matches SPI0, which works out-of-the-box with the Arduino-Pico core.
Preparing the SD Card (Important!)
Your SD card must be FAT32.
Recommended Steps
- Remove all existing partitions
- Create one primary partition (MBR)
- Format as FAT32
- For cards >32GB, use tools like Rufus or GUIFormat
Common Mistakes
| Issue | Symptom | Fix |
|---|---|---|
| exFAT format | SD init FAILED | Reformat to FAT32 |
| GPT partition | Card not detected | Convert to MBR |
| Loose card | No response | Reinsert firmly |
FAQs
Q: Why doesn’t my 64GB SD card work? Most large cards ship as exFAT. Reformat to FAT32.
Q: Can I share SPI with other sensors? Yes. Share MOSI/MISO/SCK and give each device a unique CS pin.
Q: Should I power the module with 5V? No. Always use 3.3V with the Pico.
Q: Maximum supported SD card size? FAT32 up to 32GB (larger cards work if reformatted).
For more in-depth tutorial : Raspberry Pi Pico sd card Module