题解 | #4位数值比较器电路#

`timescale 1ns/1ns

module comparator_4(
    input        [3:0]       A       ,
    input       [3:0]        B       ,
 
     output     reg        Y2    , //A>B
    output   reg        Y1    , //A=B
    output   reg       Y0      //A<B
);
    always @(*) begin
        if(A==B) begin
           Y0 = 0;
           Y1 = 1;
           Y2 = 0;
        end
        else if(A[3]>B[3]) begin
           Y0 = 0;
           Y1 = 0;
           Y2 = 1;
        end
        else begin
            if(A[3]<B[3]) begin
               Y0 = 1;
               Y1 = 0;
               Y2 = 0;     
            end
            else begin
                if(A[2]>B[2]) begin
                   Y0 = 0;
                   Y1 = 0;
                   Y2 = 1;
                end
                else begin
                    if(A[2]<B[2]) begin
                       Y0 = 1;
                       Y1 = 0;
                       Y2 = 0;     
                    end
                    else begin
                        if(A[1]>B[1]) begin
                           Y0 = 0;
                           Y1 = 0;
                           Y2 = 1;
                        end
                        else begin
                            if(A[1]<B[1]) begin
                               Y0 = 1;
                               Y1 = 0;
                               Y2 = 0;   
                            end
                            else begin
                                if(A[0]>B[0]) begin
                                   Y0 = 0;
                                   Y1 = 0;
                                   Y2 = 1;
                                end
                                else begin
                                   Y0 = 1;
                                   Y1 = 0;
                                   Y2 = 0;
                                end
                            end
                        end
                    end
                end
            end
        end
    end
endmodule