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29 lines
704 B
Verilog
29 lines
704 B
Verilog
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module test;
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parameter BYTES = 2;
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localparam mxbit = BYTES*8-1;
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function integer clog2;
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input value;
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integer value;
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for (clog2=0; value>0; clog2=clog2+1) value = value >> 1;
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endfunction
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// This is not recognized as a constant function call!
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localparam cntrw = clog2(mxbit);
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integer tmp;
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initial begin
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tmp = mxbit;
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$display("The maximum bit is %0d and uses a %0d bit counter", mxbit, cntrw);
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$display("clog2 does works here! Got %0d, should be %0d.", clog2(mxbit), clog2(tmp));
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if (cntrw !== clog2(tmp)) begin
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$display("FAILED -- cntrw=%0d", cntrw);
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$finish;
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end
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$display("PASSED");
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$finish;
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end
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endmodule
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