EMD6.1 and USB on 9150-SDK & 9250-SDK

Hi,

I'm trying to get data out of EMD6.1 from either the 9150 SDK or 9250 SDK PCBs to a PC running Windows 7. From the code in mllite_test.c it appears that it is waiting for a USB connection:
/* Wait for enumeration. */
while (USB_connectionState() != ST_ENUM_ACTIVE);

However I cannot find a PC end USB driver anywhere or any mention of it, except a couple of posts in the forum from a few years ago about having to implement your own. Is this still true? If so, why does it appear that EMD6.1 is waiting for a USB connection?

Thanks,
Ian