Hi there,When I simulate the ALTFP_MULT and ALTFP_ADD_SUB megafunctions in modelsim (directly from my testbench, not through my main design) I get zero results from both. Has anyone else encountered this, or perhaps have any ideas why this might be happening? I'm using this code to simulate them: --- Quote Start --- FIRadd addtest( add_rst, add_en, CLOCK_50, dataa, datab, add_result ); initial begin add_rst = 1'b1; add_en = 1'b0; dataa = 32'h00000000; datab = 32'h00000000; # 50ns; add_rst = 1'b0; add_en = 1'b1; dataa = 32'h0000000F; datab = 32'h0000F001; end --- Quote End ---
My fix was fairly design specific. That is, I fixed a part of my design that drove these units and then they started synthesising properly.As it was a little while back, the most I remember it being was that the registers that drove my ALTFP_MULT (which then fed the adders) were incorrectly specified. Once I fixed this small issue, everything else fell into place. I wish I could give more information then that. I wish you the best of luck though, I know how frustrating it is!