if (!rx_busy && !rx_d2) begin
      rx_busy       <= 1;
      rx_sample_cnt <= 1;
      rx_cnt        <= 0;
    end
    // Start of frame detected, Proceed with rest of data
    if (rx_busy) begin
       rx_sample_cnt <= rx_sample_cnt + 1;
       // Logic to sample at middle of data
       if (rx_sample_cnt == 7) begin
          if ((rx_d2 == 1) && (rx_cnt == 0)) begin
            rx_busy <= 0;
          end else begin
            rx_cnt <= rx_cnt + 1;
            // Start storing the rx data
            if (rx_cnt > 0 && rx_cnt < 9) begin
              rx_reg[rx_cnt - 1] <= rx_d2;
            end
            if (rx_cnt == 9) begin
               rx_busy <= 0;
               // Check if End of frame received correctly
               if (rx_d2 == 0) begin
                 rx_frame_err <= 1;
               end else begin
                 rx_empty     <= 0;
                 rx_frame_err <= 0;
                 // Check if last rx data was not unloaded,
                 rx_over_run <= (rx_empty) ? 0 : 1;
               end
            end
          end
       end
    end
end
if (!rx_enable) begin
    rx_busy <= 0;
end
end

// UART TX Logic
always @ (posedge txclk or posedge reset)
if (reset) begin
tx_reg        <= 0;
tx_empty      <= 1;
tx_over_run   <= 0;
tx_out        <= 1;
tx_cnt        <= 0;
end else begin
   if (ld_tx_data) begin
      if (!tx_empty) begin
        tx_over_run <= 0;
      end else begin
        tx_reg   <= tx_data;
        tx_empty <= 0;
      end
   end
   if (tx_enable && !tx_empty) begin
     tx_cnt <= tx_cnt + 1;
     if (tx_cnt == 0) begin
       tx_out <= 0;
     end
     if (tx_cnt > 0 && tx_cnt < 9) begin
        tx_out <= tx_reg[tx_cnt -1];
     end
     if (tx_cnt == 9) begin
       tx_out <= 1;
       tx_cnt <= 0;
       tx_empty <= 1;
     end
   end
   if (!tx_enable) begin
     tx_cnt <= 0;
   end
end

endmodule

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