module uart_rx_tb;

localparam BIT_RATE = 9600;
localparam BIT_P    = (1000000000/BIT_RATE);

localparam CLK_HZ   = 15000000;
localparam CLK_P    = 1000000000/ CLK_HZ;

logic clk = 0;
logic reset = 1'b0;
logic enable = 1'b0;
logic rxd = 1'b0;
logic rx_break;
logic rx_valid;
logic [7:0] data = 0;
logic [7:0] data_set = 8'b10101010;

always #(CLK_P/2) clk = !clk;

task send_byte;
    input [7:0] to_send;
    integer i;
    begin
        $display("Sending byte: %d at time %d", to_send, $time);

        #BIT_P;  rxd = 1'b0;
        for(i=0; i < 8; i = i+1) begin
            #BIT_P;  rxd = data_set[i];

            $display("    Bit: %d at time %d", i, $time);
        end
        #BIT_P;  rxd = 1'b1;
        #1000;
    end
endtask

initial begin
    reset = 1'b0;
    repeat(5) @(posedge clk);
    reset = 1'b1;
    repeat(5) @(posedge clk);
    
    send_byte(data_set);
end

uart_rx rx(
  .clk(clk),
  .resetn(reset),
  .uart_rxd(rxd),
  .uart_rx_en(enable),
  .uart_rx_break(rx_break),
  .uart_rx_valid(rx_valid),
  .uart_rx_data(data));

endmodule