Posted on August 01, 2013 at 08:09I've read that before.
I think the problem stems from the fact that it doesn't work if you try to use the supplied class drivers, i.e create a composite device descriptor and then in the relevant callbacks call the correct class function for that callback depending on which interface the function call was for.
I've searched the web and there was a post by a guy called Tsuneo who if you've ever done any USB searching will know that he's a bit of a guru in these matters - somebody else had asked the same question and his response was along the lines of:
''The library is broken because there's not enough separation between the layers, there are bits of code that are duplicated - it's obvious that ST have not had a working composite device with this code''
Which ties in with why there is not a composite device example! I have no doubt that if I were to implement my *own* class drives for MSC & HID using your libraries then I could get it to work, but then I'd be re-inventing the wheel and I'd rather use your MSC driver than spend X weeks writing own. Beside, I already had to modify the HID driver because it's very specific to being a mouse (or keyboard, I can't remember what now) and I needed a vendor defined one, so I already did that months ago.
I suppose the question I should have asked was:
Has anybody managed to make a composite USB+HID device using the class drivers supplied in the ST USB library.
As I mentioned before, the USB library for the 3 series is different and is obviously architected better because it does include an example.
I can't believe that such a basic operation has been omitted from the library for the F2XX/F4XX....
Anybody in ST who works on the USB library care to fix this?
🙂Adrian
