`timescale 1ns/1ns module encoder_0( input [8:0] I_n , output reg [3:0] Y_n ); always@(*)begin casex(I_n) 9'b1_1111_1111 : Y_n = 4'b1111; 9'b0_xxxx_xxxx : Y_n = 4'b0110; 9'b1_0xxx_xxxx : Y_n = 4'b0111; 9'b1_10xx_xxxx ...