TM4C1294NCPDT: USB Host Serial for TM4C129

Hi:

I was able to retrieve an example of usb host serial for usb_host_serial for the TM4C129.  It was prepared by Ralph Jacobi

The thread is here:

http://e2e.ti.com/support/microcontrollers/other/f/908/p/887651/3283470#3283470

My questions are follows:

1) The demo is reading and writing USB data from polling in the main loop.  How can I extend this demo to use interrupt service function to read/write from/to ring buffers, just similar to the USB Device Serial?

2) The demo is using the USBHCDCGetDataFromDevice function to retrieve USB data.  But it is calling from a blocking function called USBHCDPipeRead.  Is there any danger in using the non-blocking function, USBHCDPipeReadNonBlocking?

Dennis