[weinzierl]

They offer their own file system implementation (emFile) which supports either their own storage format (EFS) or FAT. The BigFAT article is posted in the emFile section of their website.

My suspicion is that customers are bugging them to support large files in emFile and they don't want to pay the license fee for exFAT. I think they even can't do that with their current licensing model, which is one-time per product (not item) or product-family payment.

EDIT: I tried to find out if Microsoft's exFAT is licensed per product or per unit and I found that it used to be a 300000 USD flat fee in 2009 but seems to be free since 2019. So my theory from above has no basis and I wonder why Segger does not simply implement exFAT?

[noAnswer]

It is not true that is "free since 2019".

Source:

https://www.microsoft.com/en-us/legal/intellectualproperty/t...

https://www.paragon-software.com/exfat-license/

https://en.wikipedia.org/wiki/ExFAT#Legal_status

You maybe of the hook if you use Linux >= 5.7. And it seem that you are of the hook if you are a member of the Open Invention Network (OIN).

But SEGGER's embOS is not based on Linux and their costumers a OEMs themselves. So their costumers would need to be OIN members or pay royalties to MS.

[weinzierl]

This is interesting, thanks. So the Linux kernel contains essentially non-free code that is, despite being under GPL, in effect not usable by others because of patents.