fopen cannot write memroy card

Ok, the last info updated:
If comment the code of usb0 (init, connect), then I can handle the file with these functions (open/read/write).

Then, the question is: how to make these two work at the same time? I use the code all from MDK-Middleware 7.0.0.

Ok, the last info updated:
If comment the code of usb0 (init, connect), then I can handle the file with these functions (open/read/write).

Then, the question is: how to make these two work at the same time? I use the code all from MDK-Middleware 7.0.0.

If you can use Middleware then i assume you have a valid MDK PRO license.

In that case, contact keil support directly

Note that for a USB file system, the PC assumes it owns the file system which allows it to cache data from the memory.

How often have you seen a USB thumb drive that suddenly modifies files or adds files without the PC you connected it to actually accessing the drive?

The way to allow multiple sources to perform updates to the same file system would basically be to implement a networked server. A computer that accesses a server knows that the information is shared, so any information not explicitly locked may be changed by someone else at any time.

Thanks for your reply, Per Westermark!

The device we are developing, will power up when plugging into usb port.
And, it allows user to enter mass storage mode manually.

So, the user may do some options (create/delete/rename/...) during the usb0 is on.
If, I say if, the file system in the MDK does not allow to do that, then we will try to add some prompt to tell the user avoid a try.

Thanks for your reply, Sankalp Agarwal!

Yes, I have. But, I like collecting info from forum before turning to the tech support.
I always think that there're lots of people who know a lot & are pleased to help others. Sometimes, the problem comes out when I missing something important. So, anyone's thought is helpful at some point. And I can learn a lot from them.