Grand Central M4 Express + SDIO Breakout

The Adafruit Grand Central M4 Express supports SDIO mode with the SDIO Breakout Board.  First, wire the two together as shown:

  • Board 3.3 to breakout 3V
  • Board GND to breakout GND
  • Board D32 to breakout CLK
  • Board D33 to breakout CMD
  • Board D8 to breakout D0
  • Board D29 to breakout D1
  • Board D20 to breakout DAT2
  • Board D21 to breakout D3

To mount the SD card, use the following code.  Remember to put it in the file mount_sd.py on CIRCUITPY so you can easily call it from code.py or the REPL with import mount_sd.

Download: file
import board
import sdioio
import storage

sdcard = sdioio.SDCard(
    clock=board.SDIO_CLOCK,
    command=board.SDIO_COMMAND,
    data=board.SDIO_DATA,
    frequency=25000000)

vfs = storage.VfsFat(sdcard)

Adafruit Micro SD SPI or SDIO Card Breakout Board - 3V ONLY!

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Micro SD cards and microcontrollers go together like micro-peanutbutter-and-jelly: SD cards are inexpensive, durable, easy to find at any shop, come in many sizes and can plug into any...
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Adafruit Grand Central M4 Express featuring the SAMD51

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Are you ready? Really ready? Cause here comes the Adafruit Grand Central featuring the Microchip ATSAMD51. This dev board is so big, it's not...
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SD/MicroSD Memory Card (8 GB SDHC)

PRODUCT ID: 1294
Add mega-storage in a jiffy using this 8 GB class 4 micro-SD card. It comes with a SD adapter so you can use it with any of our shields or adapters. Preformatted to FAT so it works out...
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This guide was first published on Jul 31, 2020. It was last updated on 2020-07-31 12:38:51 -0400.
This page (Grand Central M4 Express + SDIO Breakout) was last updated on Jul 30, 2020.