Problem about file create on nRF52840

[Blance]

usbd_msc.7z

Hello everyone:

The problem is still not resolved

Test broad is PCA10056

Test code was modified by \SDK17.0\examples\peripheral\usbd_msc\pca10056\blank\ses

Try to create a directory and write a file on this

Open txt file like under picture,data damage on address 0x3200~0x3400 ,What am I doing wrong?

[Hung Bui]

Hi Blance, 
I tried your example here on a PCA10059 but I don't see the issue. 
Attached is the file.
Have you tried to test on another board /another QSPI flash chip ? 

0041C6.TXT

[Blance]

Hi Hung:

my file content is loop on 0x00 to 0xFF

and look on your address 0x3000 ~ 0x31FF

that's the issue,

[Hung Bui]

Thanks Blance.

I can see the issue now. We will need to investigate on how this happened. Unfortunately our developers on QSPI and USB are on vacation so we would need some time to look into this. 

[Blance]

Hi Hung,

Thanks for your reply, this problem is easy to reproduce, but few people pay attention?

In addition, tests were conducted, and if the file is not written to the folder, but is changed to the root directory, the possibility of a problem is much lower.

[Blance]

Hi All:

Add the test to continuously write files to the root directory, the content is also 0x00~0xFF loop,
4k bytes are written once,
After writing 400 times, whether the read data content meets the 0x00~0xFF cycle,

if yes, the number of successes is +1, otherwise the number of failures is +1

Create a new file after the comparison is over, if the memory is insufficient, delete the oldest file

Performing this test on my personal hardware can still reproduce the abnormal file problem

format setting FAT12 4096 Bytes

three device test at same time,and stop test when get fail,finally I get same result 

"success: 62, fail: 1"

I think there may be incompatibility between QSPI and FATFS
The address needs to be aligned to 4 Bytes. This requirement is suspicious
Can someone provide an interface that does not need to be aligned with 4 Bytes?