sdioio – Interface to an SD card via the SDIO bus
Available on these boards
- class sdioio.SDCard(clock: microcontroller.Pin, command: microcontroller.Pin, data: Sequence[microcontroller.Pin], frequency: int)
SD Card Block Interface with SDIO
Controls an SD card over SDIO. SDIO is a parallel protocol designed for SD cards. It uses a clock pin, a command pin, and 1 or 4 data pins. It can be operated at a high frequency such as 25MHz. Usually an SDCard object is used with
storage.VfsFatto allow file I/O to an SD card.Construct an SDIO SD Card object with the given properties
- Parameters:
Example usage:
import os import board import sdioio import storage sd = sdioio.SDCard( clock=board.SDIO_CLOCK, command=board.SDIO_COMMAND, # Note that board.SDIO_DATA is a tuple of four pins, not an individual pin. data=board.SDIO_DATA, # On some boards, the data pins are named individually. Use this line instead. #data=(board.SDIO_DATA0, board.SDIO_DATA1, board.SDIO_DATA2, board.SDIO_DATA3), frequency=25000000) vfs = storage.VfsFat(sd) storage.mount(vfs, '/sd') os.listdir('/sd')
- configure(frequency: int = 0, width: int = 0) None
Configures the SDIO bus.
- Parameters:
frequency (int) – the desired clock rate in Hertz. The actual clock rate may be higher or lower due to the granularity of available clock settings. Check the
frequencyattribute for the actual clock rate.width (int) – the number of data lines to use. Must be 1 or 4 and must also not exceed the number of data lines at construction
Note
Leaving a value unspecified or 0 means the current setting is kept
- count() int
Returns the total number of sectors
Due to technical limitations, this is a function and not a property.
- Returns:
The number of 512-byte blocks, as a number
- readblocks(start_block: int, buf: circuitpython_typing.WriteableBuffer) None
Read one or more blocks from the card
- Parameters:
start_block (int) – The block to start reading from
buf (WriteableBuffer) – The buffer to write into. Length must be multiple of 512.
- Returns:
None
- writeblocks(start_block: int, buf: circuitpython_typing.ReadableBuffer) None
Write one or more blocks to the card
- Parameters:
start_block (int) – The block to start writing from
buf (ReadableBuffer) – The buffer to read from. Length must be multiple of 512.
- Returns:
None
- frequency: int
The actual SDIO bus frequency. This may not match the frequency requested due to internal limitations.
- __exit__() None
Automatically deinitializes the hardware when exiting a context. See Lifetime and ContextManagers for more info.