USB stack capacity

[antonychen2008]

Dear Sir:

I am implementing a USB Host function to support USB mass storage device, I need to know how many capacity supported by our MQX USB host stack and file system.

Thanks

[danielchen]

Hi Andy C

Could you please share us your MQX version and Board information, which USB stack you are using, usb_v2 or old usb?

Regards

Daniel

[antonychen2008]

Thank you for your feedback, I am using TWR-K64 and USB_v2

[danielchen · Accepted solution]

Hi Andy:

There are no known limits expect those of FAT32 itself. But as with any USB device, due to various small incompatibilities and deviations from standard, they should do testing with stick they anticipate to use - if that is possible.

Also as a note, that with sticks above 4GB there may be issues with obtaining free space (should use IO_IOCTL_FREE_CLUSTERS and IO_IOCTL_GET_CLUSTER_SIZE instead of IO_IOCTL_FREE_SPACE)H

Hope it helps

Regards

Daniel