pluto_hdl_adi/library/common/util_pulse_gen.v

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`timescale 1ns/1ps

module util_pulse_gen #(

  parameter       PULSE_WIDTH = 7,
  parameter       PULSE_PERIOD = 100000000) (

  input                   clk,
  input                   rstn,

  output  reg             pulse);


  // internal registers

  reg     [(PULSE_WIDTH-1):0]  pulse_width_cnt = {PULSE_WIDTH{1'b1}};
  reg     [31:0]               pulse_period_cnt = 32'h0;

  wire                         end_of_period_s;

  // a free running pulse generator

  always @(posedge clk) begin
    if (rstn == 1'b0) begin
      pulse_period_cnt <= 32'h0;
    end else begin
      pulse_period_cnt <= (pulse_period_cnt < PULSE_PERIOD) ? (pulse_period_cnt + 1) : 32'b0;
    end
  end

  assign  end_of_period_s = (pulse_period_cnt == (PULSE_PERIOD - 1)) ? 1'b1 : 1'b0;

  // generate pulse with a specified width

  always @(posedge clk) begin
    if (rstn == 1'b0) begin
      pulse_width_cnt <= 0;
      pulse <= 0;
    end else begin
      pulse_width_cnt <= (pulse == 1'b1) ? pulse_width_cnt + 1 : {PULSE_WIDTH{1'h0}};
      if(end_of_period_s == 1'b1) begin
        pulse <= 1'b1;
      end else if(pulse_width_cnt == {PULSE_WIDTH{1'b1}}) begin
        pulse <= 1'b0;
      end
    end
  end

endmodule