Introduction

CircuitPython driver for SD cards. This implements the basic reading and writing block functionality needed to mount an SD card using storage.VfsFat.

Dependencies

This driver depends on:

• Adafruit CircuitPython 2.0.0+
• Bus Device

Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle.

Usage Example

Mounting a filesystem on an SD card so that its available through the normal Python ways is easy.

Below is an example for the Feather M0 Adalogger. Most of this will stay the same across different boards with the exception of the pins for the SPI and chip select (cs) connections.

import adafruit_sdcard
import busio
import digitalio
import board
import storage

# Connect to the card and mount the filesystem.
spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
cs = digitalio.DigitalInOut(board.SD_CS)
sdcard = adafruit_sdcard.SDCard(spi, cs)
vfs = storage.VfsFat(sdcard)
storage.mount(vfs, "/sd")

# Use the filesystem as normal.
with open("/sd/test.txt", "w") as f:
    f.write("Hello world\n")

Sharing the SPI bus with other devices

Important

If the same SPI bus is shared with other peripherals, it is important that the SD card be initialized before accessing any other peripheral on the bus. Failure to do so can prevent the SD card from being recognized until it is powered off or re-inserted.

Documentation

API documentation for this library can be found on Read the Docs.

For information on building library documentation, please check out this guide.

Contributing

Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.