30. PWM with 4-bit Resolution

How do you plan to solve it?

/*Write your code here*/
module pwm4_basic(
    input wire clk, 
    input wire rst, 
    input wire [3:0] duty,
    output reg pwm_out 
);
    reg [3:0] counter;
    always @(posedge clk) begin
        pwm_out <= rst ? 1'b0 : (counter < duty);
        counter <= rst ? 4'b00 : (counter + 4'd1);
    end

endmodule