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
			Y0 = 1'b0;
			Y1 = 1'b0;
			Y2 = 1'b0;
		if(A[3] > B[3])  Y2 = 1'b1;
		else if(A[3] < B[3]) Y0 = 1'b1;
		else if(A[3] == B[3]) 
			begin
				if(A[2] > B[2])  Y2 = 1'b1;
				else if(A[2] < B[2]) Y0 = 1'b1;
				else if(A[2] == B[2]) 
					begin
						if(A[1] > B[1])  Y2 = 1'b1;
						else if(A[1] < B[1]) Y0 = 1'b1;
						else if(A[1] == B[1]) 
							begin
								if(A[0] > B[0])  Y2 = 1'b1;
							else if(A[0] < B[0]) Y0 = 1'b1;
							else if(A[0] == B[0]) Y1 = 1'b1;
							end
						else
						begin
							Y0 = 1'b0;
							Y1 = 1'b0;
							Y2 = 1'b0;
						end
					end
				else
					begin
						Y0 = 1'b0;
						Y1 = 1'b0;
						Y2 = 1'b0;
					end
			end
		else 
			begin
				Y0 = 1'b0;
				Y1 = 1'b0;
				Y2 = 1'b0;
			end
	end
endmodule