This package provides the driver for sdcard/mmc with SPI connection.
examples/sdcard/console shows a low-level access example.
examples/sdcard/tinyfs shows an example of using fatfs to read FAT32.

If you use this package, you need to set default-stack-size in targets/*.json.
For example, targets/wioterminal.json has the following configuration.

{
    "inherits": ["atsamd51p19a"],
    "build-tags": ["wioterminal"],
    "flash-1200-bps-reset": "true",
    "flash-method": "msd",
    "msd-volume-name": "Arduino",
    "msd-firmware-name": "firmware.uf2",
    "default-stack-size": 2048
}