Three modules

Problem statement

You are given a module my_dff with two inputs and one output (that implements a D flip-flop). Instantiate three of them, then chain them together to make a shift register of length 3. The clk port needs to be connected to all instances.

The module provided to you is: module my_dff ( input clk, input d, output q );

Note that to make the internal connections, you will need to declare some wires. Be careful about naming your wires and module instances: the names must be unique.

module top_module ( input clk, input d, output q );

endmodule

Solution

module top_module ( input clk, input d, output q );
    wire w1,w2;
    my_dff inst1 (clk,d,w1);
    my_dff inst2 (clk,w1,w2);
    my_dff inst3 (clk,w2,q);
endmodule