Wire4

Something need to be noticed

• When you have multiple assign statements, the order in which they appear in the code does not matter.

Unlike a programming language, assign statements ("continuous assignments") describe connections between things, not the action of copying a value from one thing to another.

Problem statement

Create a module with 3 inputs and 4 outputs that behaves like wires that makes these connections:

a -> w

b -> x

b -> y

c -> z

module top_module( 
    input a,b,c,
    output w,x,y,z );

endmodule

Solution

module top_module( 
    input a,b,c,
    output w,x,y,z );
    assign {w,x,y,z} = {a,b,b,c};
endmodule

• If we're certain about the width of each signal, using the concatenation operator is equivalent and shorter: assign {w,x,y,z} = {a,b,b,c};