USB Composite device application development using MQX 3.4 USB device stack

Discussion created by SUBHASHINI MANNE on Jan 29, 2010
Latest reply on Apr 3, 2012 by Suketu Patel


 We have sample code for Serial over USB and MSD class  using MQX 3.4 USB device stack.

My requirement is I have  to design composite device application  which supports CDC+MSD.

I started working  on enumeration portion.


I am using virtual comport sample code as base code.

I modified usb_descriptor.c and usb_descriptor.h file for composite device support.


For Virtual comport application sample code USB_Class_CDC_Init() function.


To add mass stoarge support I referred MSC sample code and I defien required variables and passed that information to USB_Class_MSC_Init() function. 

When I call  USB_Class_MSC_Init() which initialize the mass storage device driver with call back functions,device enumeration is failing.


 What are all the thing sI have to take care for the composite device application  development?