`include Compiler Directive

Directs the compiler to compile the contents of a text file as if they had been inserted directly in the source code at the same place as the `include directive.

Syntax ( Key to Notation )

`include "FileName"

Where

Anywhere. The file contents must make sense when included.

Rules

Only white space or a comment may appear on the same line as `include.
The file name can include a full or relative directory path in the host operating system.
`include may be nested, although implementations may impose a limit of not less than 15 levels.

Tips

Put shared parameter or `define declarations in a separate file, and include wherever they are required.

Example

module FSM (Clock, Reset,...);
  input Clock, Reset...;

  `include "definitions.v"  // Parameters ResetState
                            // StartState etc.

  reg [3:0] State;

  always @(posedge Clock)
    if (!Reset)
      State <= ResetState;
    else
      case (State)
        ResetState : ...;
        StartState : ...;
        ...
      endcase

endmodule

`include Compiler Directive

Where

Rules

Tips

Example

See Also