30. PWM with 4-bit Resolution

How do you plan to solve it?

/*Write your code here*/
module pwm4_basic (
    input wire clk,rst,
    input wire [3:0] duty,
    output reg pwm_out
);
reg [3:0] counter;
always @(posedge clk) begin
    if(rst==1'b1) begin
        counter<=4'b0000;
        pwm_out<=1'b0;
    end
    else begin
        counter<=counter+1'b1;
    if (counter<duty) begin 
        pwm_out<=1'b1;
    end
    else  begin 
        pwm_out<=1'b0;
    end
    end
end
endmodule