FPGA设计串口收发实验Verilog逻辑源码Quartus工程文件+文档说明，FPGA型号Cyclone4E系列中的EP4CE6F17C8，Quartus版本17.1。
module uart_test(
input clk,
input rst_n,
input uart_rx,
output uart_tx
);
parameter CLK_FRE = 50;//Mhz
localparam IDLE = 0;
localparam SEND = 1; //send HELLO ALINX\r\n
localparam WAIT = 2; //wait 1 second and send uart received data
reg[7:0] tx_data;
reg[7:0] tx_str;
reg tx_data_valid;
wire tx_data_ready;
reg[7:0] tx_cnt;
wire[7:0] rx_data;
wire rx_data_valid;
wire rx_data_ready;
reg[31:0] wait_cnt;
reg[3:0] state;
assign rx_data_ready = 1'b1;//always can receive data,
//if HELLO ALINX\r\n is being sent, the received data is discarded
always@(posedge clk or negedge rst_n)
begin
if(rst_n == 1'b0)
begin
wait_cnt <= 32'd0;
tx_data <= 8'd0;
state <= IDLE;
tx_cnt <= 8'd0;
tx_data_valid <= 1'b0;
end
else
case(state)
IDLE:
state <= SEND;
SEND:
begin
wait_cnt <= 32'd0;
tx_data <= tx_str;
if(tx_data_valid == 1'b1 && tx_data_ready == 1'b1 && tx_cnt < 8'd12)//Send 12 bytes data
begin
tx_cnt <= tx_cnt + 8'd1; //Send data counter
end
else if(tx_data_valid && tx_data_ready)//last byte sent is complete
begin
tx_cnt <= 8'd0;
tx_data_valid <= 1'b0;
state <= WAIT;
end
else if(~tx_data_valid)
begin
tx_data_valid <= 1'b1;
end
end
WAIT:
begin
wait_cnt <= wait_cnt + 32'd1;
if(rx_data_valid == 1'b1)
begin
tx_data_valid <= 1'b1;
tx_data <= rx_data; // send uart received data
end
else if(tx_data_valid && tx_data_ready)
begin
tx_data_valid <= 1
2021-04-12 20:03:54
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