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comparisonverilog

How to compare negative numbers (2's complement) in verilog?

I have the following comparison statement in verilog, which works fine (positive comparison) 

if((count_cc >= 13'b0000000011110)&&(count_cc <= 13'b0000000111100)) //30,60
begin
level=4'b0010; //level 2
end

However, when I use 2's complement, it does not work, 

if((count_cc >= 13'b1111111100100)&&(count_cc <= 13'b1111111110110)) //-10 , -28
begin
level=4'b0101;  //level 5
end

Any guidance would be helpful.

Solution

  • Assuming count_cc is already declared signed, use

    if((count_cc >= 13'sb1111111100100)&&(count_cc <= 13'sb1111111110110)) //-10 , -28
begin
  level=4'b0101;  //level 5
end

    of course, this would also work

    if((count_cc >= -10)&&(count_cc <= -28)