hello.v

module top(
           input clk_12M,
           output LED1,
           output LED2,
           output LED3,
           output LED4,
           output LED5,
           output LED6,
           output LED7,
           output LED8,
           input UART_RX,
           output UART_TX
           )
  ;

   localparam UART_OVERSAMPLING = 26;
   localparam UART_CLK_DIV = 104;

   reg uart_clk115200 = 0;
   reg [6:0] divider = 0;

   reg [24:0] cur = 0;
   wire [4:0] pos;

   initial begin
      cur = 0;
   end

   assign pos = cur[24:21];

   assign LED1 = (pos==0);
   assign LED2 = (pos==1) | (pos==13);
   assign LED3 = (pos==2) | (pos==12);
   assign LED4 = (pos==3) | (pos==11);
   assign LED5 = (pos==4) | (pos==10);
   assign LED6 = (pos==5) | (pos==9);
   assign LED7 = (pos==6) | (pos==8);
   assign LED8 = (pos==7);

   always @(posedge clk_12M)
     begin
        if (pos == 14) begin cur = 0; end
        else begin cur = cur+1; end
     end

   always @(posedge clk_12M)
     begin
        if (divider == UART_CLK_DIV-1) begin
           divider = 0;

           if (data_counter >= 9) begin
              data_counter = 0;

              if (char_counter == 13) begin
                 char_counter = 0;
              end else begin
                 char_counter = char_counter+1;
              end
           end else begin
              data_counter = data_counter+1;
           end
        end else begin
           divider = divider+1;
        end
     end

   always @(posedge clk_12M)
     begin
        if (divider < UART_CLK_DIV/2) begin
           uart_clk115200 = 1;
        end else begin
           uart_clk115200 = 0;
        end
     end

   wire [7:0] out_char;

   assign out_char = ((char_counter == 0)?8'h48:
                      (char_counter == 1)?8'h65:
                      (char_counter == 2)?8'h6c:
                      (char_counter == 3)?8'h6c:
                      (char_counter == 4)?8'h6f:
                      (char_counter == 5)?8'h20:
                      (char_counter == 6)?8'h57:
                      (char_counter == 7)?8'h6f:
                      (char_counter == 8)?8'h72:
                      (char_counter == 9)?8'h6c:
                      (char_counter == 10)?8'h64:
                      (char_counter == 11)?8'h21:
                      (char_counter == 12)?8'h0d: 8'h0a);

   reg [3:0] char_counter = 0;
   reg [3:0] data_counter = 0;
   wire [9:0] data = 10'b1010000010;

   assign UART_TX = data_counter == 0?0:
                    data_counter == 9?1:
                    out_char[data_counter-1];
endmodule