Storage & SD¶
The Cyber Fidget has a microSD card slot for app storage, asset loading, and data logging.
Draft section
THIS SECTION IS STILL IN DRAFT
Recommended card specs¶
| Spec | Recommendation |
|---|---|
| Format | FAT32 (required) |
| Size | 1 GB – 32 GB (FAT32 max). Larger cards may need manual formatting to FAT32. |
| Speed | Class 4 or higher. Class 10 / UHS-I recommended for faster read/write. |
| Form factor | microSD (not full-size SD) |
Tested brands
Phison-based cards in the 4–32 GB range work well. Avoid ultra-cheap no-name cards — they can have compatibility issues with SPI-mode access.
Formatting¶
Format your card as FAT32 before first use:
- Windows: Right-click the drive → Format → FAT32. For cards > 32 GB, use a tool like Rufus or SD Card Formatter.
- macOS: Disk Utility → Erase → MS-DOS (FAT).
- Linux:
mkfs.vfat /dev/sdX1
Use cases¶
- App storage — Some apps load assets (images, animation frames, sound data) from the SD card
- Data logging — Apps can write sensor data, scores, or logs to files
- File browsing — The WiFi web portal can serve files from the SD card for easy transfer
- Settings — User preferences and configuration can be persisted across power cycles
Hardware details¶
The SD card connects to the ESP32 via SPI:
| Pin | Signal |
|---|---|
| GPIO 5 | SCK (clock) |
| GPIO 19 | MOSI (data out) |
| GPIO 21 | MISO (data in) |
The SD card shares the 3.3V_RGB power rail (GPIO 2 enable), so it is powered down when the AUX regulator is disabled in deep sleep.
See also¶
- Hardware Specs — Full component list
- Pinout — GPIO assignments for SD SPI bus
- Apps — Which apps use SD card storage