Page 571 - 3-2

rx_clk_cnt <= 0;
if(rx_bit_cnt >= 8) rx_bit_cnt <= 0; // 수신데이터 bit count
else rx_bit_cnt <= rx_bit_cnt +1'b1;
end
else rx_clk_cnt <= rx_clk_cnt + 1'b1; //always 하나 빼서 할 수 있음

if ( rx_bit_cnt < 8 && rx_clk_cnt == baud_rate) // receive data
begin
rx_data_buffer[rx_bit_cnt] <= rxd;
state_rx <= 1;
end

else if (rx_bit_cnt == 8&& rx_clk_cnt == baud_rate && rxd ==
1)// stop receiving
begin
state_rx <= 0;
rx_data <= rx_data_buffer; // data 출력
end

// if stop bit is not received, clear the received data
else if (rx_bit_cnt == 8 && rx_clk_cnt == baud_rate && rxd != 1)
begin
state_rx <= 0;
rx_data_buffer <= 8'b00000000; // invalidate
end
end
end
end

always @(posedge clk, negedge reset)
begin
if(!reset)
begin
Light<=2'b0;
fan<=2'b00;
B_D<=1'b0;
end

else
begin
if(rx_data=="A")
begin
//fan<=fan;
Light<=2'b11;
B_D<=1'b0;

- 571 -