As you said, composite device is a key to solve this difficulty on USB application.

We can make a composite device, combining generic device drivers and HID.
In this topic, I showed the procedure in details.

"USB Composite Device" from SiLabs forum
http://www.cygnal.org/ubb/Forum9/HTML/001050.html

MS provide two useful example, BulkUSB and ISOUSB, in WinDDK.
These examples provide generic device drivers for bulk and isochronous. They works without any modification; just compile it using the C compiler attached to the DDK.

"DDK - Windows Driver Development Kit" from MS
http://www.microsoft.com/whdc/DevT...fault.mspx

Using HID in addition to these generic drivers, we can make various composite devices which support any type of endpoints, EP0, interrupt, bulk and iso. That is, we can make custom USB applications without device driver development, using composite device.


Surely, the requirement of a custom device driver development is not limited to the USB transfer support. For example, a streaming buffer is often implemented on the device driver side to support 'real time' transfer. In this topic, I showed a method to make up a streaming buffer between host application and a generic bulk device driver, using multiple OVERLAPPED call simultaneously.

"Non-stop USB bulk streaming and USBXpress 3.0.3"
http://www.cygnal.org/ubb/Forum9/HTML/001112.html

As seen in this instance, we can work out in this extent on the host application side.

I don't say that the device driver development is not required at all. But I believe we can find a way to work around it.

Tsuneo