جمع کننده دو بیتی:

module full_adder1b(a,b,cin,sum,cout);
  input a,b,cin;
  output sum,cout;
  wire w1,w2,w3;
  xor (sum,a,b,cin);
  and (w1,a,b),(w2,a,cin),(w3,b,cin);
  or (cout,w1,w2,w3);
endmodule

جمع کننده چهار بیتی:

module fulladder(sum, cout, a, b, cin); 
output sum, cout; 
input a, b, cin; 
wire s1, c1, s2; 
xor (s1, a, b); 
and (c1, a, b); 
xor(sum, s1, cin); 
and(s2, s1, cin); 
or(cout, s2, c1); 
endmodule
module fulladder4(sum,cout,a,b,cin);
  output [3:0] sum;
  output cout;
  input [3:0] a,b;
  input cin;
  wire c1, c2, c3;
  fulladder fa0(sum[0], c1, a[0], b[0], cin);
  fulladder fa1(sum[1], c2, a[1], b[1], c1);
  fulladder fa2(sum[2], c3, a[2], b[2], c2);
  fulladder fa3(sum[3], cout, a[3], b[3], c3);
  endmodule