2位元比較器之compare_2b

module top;
reg A1,A0,B1,B0;
wire A_lt_B,A_gt_B,A_eq_B;
compare_2b m1(A_lt_B,A_gt_B,A_eq_B,A1,A0,B1,B0);
initial
begin
A1=0;
A0=0;
B1=0;
B0=0;

#2000 $finish;
end
always
#30 A1=~A1;
always
#40 A0=~A0;
always
#50 B1=~B1;
always
#60 B0=~B0;

endmodule

module compare_2b(A_lt_B,A_gt_B,A_eq_B,A1,A0,B1,B0);
input A1,A0,B1,B0;
output A_lt_B,A_gt_B,A_eq_B;

assign A_lt_B=({A1,A0}<{B1,B0}); assign A_gt_B=({A1,A0}>{B1,B0});
assign A_eq_B=({A1,A0}=={B1,B0});
endmodule