Hey Casper, I compiled a design for the ROACH board using the 11.x toolset and saw the resource usage for DSP48Es was "366 out of 640, 57%."
There are many filters in the design, but can be thought of as having two identical signal paths. I built each signal path up into 64 bit words ready to transmit. One signal path I transmit off the 10 gbe port, the other i simply terminated. Since the compile worked and seemed to not push too many resources to the limit, I decided to add a second 10 gbe port to the design for the second signal path. now, my design does not fit with the error of "Too many comps of type DSP48E." 1) Could it be that the 10 gbe port and its registers really use a lot of DSP48Es? 2) Is it possible that since in the first design the second signal path was eventually terminated, Xilinx just never built it at all and the resource usage was misleading? 3) After the resource usage is printed to the screen, could there be anything else that gets added that takes up logic or DSP48Es? 4) Any other advice about understanding and utilizing the resource usage stats? --Laura
