题解 | #4位数值比较器电路#

使用 A & !B可以在A=1 B=0的时候返回1，比较大小，然后用^~同或比较是否一致，那么四位就可以简单的写为下面代码

`timescale 1ns/1ns

module comparator_4(
	input		[3:0]       A   	,
	input	   [3:0]		B   	,
 
 	output	 wire		Y2    , //A>B
	output   wire        Y1    , //A=B
    output   wire        Y0      //A<B
);

assign Y2 = (A[3] & !B[3]) || 
			(A[2] & !B[2] & (A[3] ^~ B[3])) ||
			(A[1] & !B[1] & (A[3] ^~ B[3]) & (A[2] ^~ B[2])) || 
			(A[0] & !B[0] & (A[3] ^~ B[3]) & (A[2] ^~ B[2]) & (A[1] ^~ B[1]));
assign Y0 = (!A[3] & B[3]) || 
			(!A[2] & B[2] & (A[3] ^~ B[3])) ||
			(!A[1] & B[1] & (A[3] ^~ B[3]) & (A[2] ^~ B[2])) || 
			(!A[0] & B[0] & (A[3] ^~ B[3]) & (A[2] ^~ B[2]) & (A[1] ^~ B[1]));
assign Y1 = (A[3] ^~ B[3]) & (A[2] ^~ B[2]) & (A[1] ^~ B[1]) & (A[0] ^~ B[0]);


endmodule