feurig - "I am less and less interested in cheap usb to serial devices and more and more interested in native usb devices."
I think I am more interested in "no-device-driver" USB than how it is implemented.
I would like to be able to use any host computer, without having to install a device driver, to program and use a microcontroller.
AFAIK, that restricts the USB devices to: USB CDC serial, USB flash drive, USB HID, and maybe a few other like midi.
Of those, USB serial and USB flash drive (mass-storage device, i.e. folders and files), can be used with existing, off-the-shelf applications, and are relatively straightforward to develop host applications for upload and interfacing (I've used C, Processing, Python and Go to interface to Arduino's USB serial).
An example use-case might be "I have built a 3D printer, controlled by an Orone-mini. I take my 3D printer to a hack-space, and someone wants to try using it from their Windows or Chrome laptop. We plug the 3D printer into their laptop, and they 'copy' their data file to the device without installing a device driver, or even an application". I don't want to spend time writing, testing and supporting device-drivers.
So I am happy to use something a bit smarter than a CP2102, as long as I don't then need to spend effort on device drivers for host platforms. I haven't got the test equipment to 'sniff' USB, so I don't feel that would be productive, and I don't want to spend my life testing all the variants of Windows+service patches to debug USB.
So, any path that:
- is relatively low-cost,
- avoids the Maple bootloader problems
- minimises the effort spent on replicating infrastructure like IDEs, tools, etc
- maximises reuse of stuff that works
- lets me use the STM32F
- avoids the need to develop software on lots of platforms
is all good news to me.