30. PWM with 4-bit Resolution

How do you plan to solve it?

module pwm4_basic (
    input  wire       clk,
    input  wire       rst,
    input  wire [3:0] duty,
    output reg        pwm_out
);

    reg [3:0] count;   // 4-bit counter

    always @(posedge clk) begin
        if (rst) begin
            count   <= 4'd0;
            pwm_out <= 1'b0;
        end 
        else begin
            // increment counter and wrap at 15 -> 0
            count <= count + 1'b1;

            // PWM output logic
            if (count < duty)
                pwm_out <= 1'b1;
            else
                pwm_out <= 1'b0;
        end
    end

endmodule