WBUS-EMMC referenceΒΆ


The eMMC chip on the WBUS-EMMC adapter board has 3825205248 bytes of capacity. It is available via the pyb.MMCard() object and must be managed manually.

To mount it on the filesystem use:

import os, pyb
os.mount(pyb.MMCard(), '/mmc')

To expose it over USB mass storage (MSC) use, eg in boot.py:

pyb.usb_mode('VCP+MSC', msc=(pyb.MMCard(),))

If the eMMC is not mounted and/or exposed on the USB MSC interface it will remain uninitialised and will draw about 25mA of current. To enable it to go into sleep mode it must be powered up via:


To reinitialise the partition and FAT table on the eMMC you can use this script: mmc_format.py