题解 | 实现3-8译码器①

`timescale 1ns/1ns

module decoder_38(
   input             E1_n   ,
   input             E2_n   ,
   input             E3     ,
   input             A0     ,
   input             A1     ,
   input             A2     ,
   
   output wire       Y0_n   ,  
   output wire       Y1_n   , 
   output wire       Y2_n   , 
   output wire       Y3_n   , 
   output wire       Y4_n   , 
   output wire       Y5_n   , 
   output wire       Y6_n   , 
   output wire       Y7_n   
);

assign Y0_n = ~(E3 & (~E2_n & ~E1_n & ~A2 & ~A1 & ~A0));
assign Y1_n = ~(E3 & (~E2_n & ~E1_n & ~A2 & ~A1 & A0));
assign Y2_n = ~(E3 & (~E2_n & ~E1_n & ~A2 & A1 & ~A0));
assign Y3_n = ~(E3 & (~E2_n & ~E1_n & ~A2 & A1 & A0));
assign Y4_n = ~(E3 & (~E2_n & ~E1_n & A2 & ~A1 & ~A0));
assign Y5_n = ~(E3 & (~E2_n & ~E1_n & A2 & ~A1 & A0));
assign Y6_n = ~(E3 & (~E2_n & ~E1_n & A2 & A1 & ~A0));
assign Y7_n = ~(E3 & (~E2_n & ~E1_n & A2 & A1 & A0));

endmodule

Yx_n为1的条件太复杂了，找Yx_n为0的条件，~Yx_n = *****，随后整体取反。