Ethernet with DSP Dev. Kit Cyclone III (no NIOS)

To generate the Ethernet frames in hardware, you need to know the PC's MAC address (that is usually found from it's IP using the ARP protocol) and compute the IP and UDP checksums.

For the USB communication, the USB part of the board isn't documented, and it doesn't seem easy. There is another thread on that subject in this forum. An alternative would be to use the embedded USB blaster in JTAG mode, and use the system console tools on the PC to directly access the Nios' memory and read the data in there. Unfortunately I'm not sure the performance will be very high...