4bit comparator using == ,>, < operator (Dataflow level)

4bit comparator using == ,>, < operator (Dataflow level)

//=====================================================
// 4bit comparator using = operator (Dataflow level)
//=====================================================
module comp_4bit(a,b,Result);
input [3:0] a,b;
output [2:0] Result;

reg [2:0]tmp;
always @(*) begin
if (a>b)
tmp<=3'b100; //a>b
else if (a==b)
tmp<=3'b010; //a=b
else
tmp<=3'b001; //a<b
end
assign Result=tmp;
endmodule

// 時間單位 100ns, 時間精確度100 ps

`timescale 100ns/100ps 

module TB;

/*

module comp_4bit(a,b,Result);

input [3:0] a,b;

output [2:0] Result;

*/

reg [3:0] a,b;

wire [2:0] Result;

integer i;

 

comp_4bit UUT(a,b,Result);

 

initial begin  

   for ( i=0;i<=256;i=i+1) 

        begin

           {a,b}  = i;

            #1;

        end

end

endmodule