[usb] Draft 0.7 of the USB spec released

[Rudolf Usselmann <rudi@asics.ws>]

I think the only thing missing now is the Setup/Config transactions
and some software models.

Here is what's new in this spec:

Added frame number and time (FRM_NAT) register
Filled in USB core behavior section
Filled in most of the flowcharts
Fixed endpoint interrupt register
Added suspend output to wishbone IF
Added names to some of the bits in the endpoint registers

The latest and greatest spec can be found here:

http://www.opencores.org/cores/usb/usb_doc.pdf


Cheers !
rudi