QUIZ

module top;
system_clock #400 clock1(a);
system_clock #200 clock1(b);
system_clock #100 clock1(c);
system_clock #50 clock1(d);
number n1(e,a,b,c,d);
endmodule
module number(e,a,b,c,d);
input a,b,c,d;
output e;
wire a1,b1,c1,d1,w1,w2,w3,w4,w5,w6;
not(a1,a);
not(b1,b);
not(c1,c);
not(d1,d);
and(w1,a1,c1,d);
and(w2,a1,b1,d);
and(w3,a,c,d);
and(w4,b1,c,d);
and(w5,a,c1,d1);
and(w6,a1,b,c,d1);
or(e,w1,w2,w3,w4,w5,w6);
endmodule
module system_clock(clk);
parameter PERIOD=100;
output clk;
reg clk;
initial
clk=0;
always
begin
#(PERIOD/2)clk=~clk;
end
always@(posedge clk)
if($time>1000)
$stop;
endmodule

二位元全加器

vicky's refegence

1位全加器

module test_adder1;

 reg a,b;
 reg carry_in ;
 wire sum;
 wire carry_out;

 adder1_behavorial A1(carry_out, sum, a, b, carry_in);

 initial
  begin

    carry_in = 0; a = 0; b = 0;
    # 100 if ( carry_out != 0 | sum !== 0)
                $display(" 0+0+0=00 sum is WRONG!");
              else
                $display(" 0+0+0=00 sum is RIGHT!");
    carry_in = 0; a = 0; b = 1;
    # 100 if ( carry_out != 0 | sum !== 1)
               $display(" 0+0+1=01 sum is WRONG!");
              else
               $display(" 0+0+1=01 sum is RIGHT!");
    carry_in = 0; a = 1; b = 0;
    # 100 if ( carry_out != 0 | sum !== 1)
               $display(" 0+1+0=01 sum is WRONG!");
              else
               $display(" 0+1+0=01 sum is RIGHT!");
    carry_in = 0; a = 1; b = 1;
    # 100 if ( carry_out != 1 | sum !== 0)
               $display(" 0+1+1=10 sum is WRONG!");
              else
               $display(" 0+1+1=10 sum is RIGHT!");
   carry_in = 1; a = 0; b = 0;
    # 100 if ( carry_out != 0 | sum !== 1)
               $display(" 1+0+0=01 sum is WRONG!");
              else
               $display(" 1+0+0=01 sum is RIGHT!");
   carry_in = 1; a = 0; b = 1;
    # 100 if ( carry_out != 1 | sum !== 0)
               $display(" 1+0+1=10 sum is WRONG!");
              else
               $display(" 1+0+1=10 sum is RIGHT!");
   carry_in = 1; a = 1; b = 0;
    # 100 if ( carry_out != 1 | sum !== 0)
               $display(" 1+1+0=10 sum is WRONG!");
              else
               $display(" 1+1+0=10 sum is RIGHT!");
   carry_in = 1; a = 1; b = 1;
    # 100 if ( carry_out != 1 | sum !== 1)
               $display(" 1+1+1=11 sum is WRONG!");
              else
               $display(" 1+1+1=11 sum is RIGHT!");
    $finish;
  end
endmodule



module adder1_behavorial (carry_out, sum, a, b, carry_in);
 input a, b, carry_in;
 output carry_out, sum;
  assign sum = (carry_in^(a^b));
  assign carry_out = (carry_in&(a^b)|a&b);
endmodule

二位元多工器行為模組

參考........

二位元行為模式

一位元多工模組

二位元多功器