counter.v

design compile synthesis user guide

module Counter (count, start, clk, rst);
/* Counter module */
  input clk;
  input rst;
  input start;
  output [15:0] count;

  wire clk;
  reg [15:0] count_N;
  reg [15:0] count;

  always @ (posedge clk or posedge rst)
    begin : counter_S
      if (rst) begin
        count = 0; // reset logic for the block
        end
      else begin
        count = count_N; // set specified registers of the block
        end
    end

  always @ (count or start)
    begin : counter_C
      count_N = count; // initialize outputs of the block
      if (start) count_N = 1; // user specified logic for the block
      else count_N = count + 1;
    end
endmodule