用Verilog实现:uart串口通信,input是一个8位数data,让在电脑显示的数据按0、1、data、2的顺序显示
时间: 2024-02-12 08:07:23 浏览: 27
下面是一个简单的 Verilog HDL 代码实现,可以实现串口通信,将输入的 8 位数 data 按照 0、1、data、2 的顺序发送到电脑上:
```
module uart_top(
input clk,
input rst_n,
input [7:0] data
);
reg [1:0] state = 2'b00;
reg [3:0] tx_data;
reg tx_busy;
// 定义状态常量
localparam IDLE = 2'b00;
localparam START = 2'b01;
localparam DATA = 2'b10;
localparam STOP = 2'b11;
// 定义波特率常量
localparam BAUD_RATE = 9600;
// 定义计数器常量
localparam DATA_BITS = 8;
localparam STOP_BITS = 1;
localparam START_BITS = 1;
localparam COUNTER_MAX = BAUD_RATE / (DATA_BITS + STOP_BITS + START_BITS);
// 定义计数器和计数器复位信号
reg [15:0] counter = 16'd0;
wire counter_rst = (counter == COUNTER_MAX);
// 定义串口发送模块
uart_tx uart_tx_inst(
.clk(clk),
.rst_n(rst_n),
.data(tx_data),
.busy(tx_busy)
);
always @(posedge clk or negedge rst_n) begin
if (~rst_n) begin
state <= IDLE;
counter <= 0;
tx_data <= 0;
tx_busy <= 0;
end else begin
case (state)
IDLE: begin
if (data == 8'h00) begin
tx_data <= 4'h0;
state <= START;
end else if (data == 8'h01) begin
tx_data <= 4'h1;
state <= START;
end else if (data != 8'h00 && data != 8'h01) begin
tx_data <= data;
state <= START;
end
end
START: begin
tx_data <= 1'b0;
state <= DATA;
end
DATA: begin
tx_data <= data;
state <= STOP;
end
STOP: begin
tx_data <= 1'b1;
state <= IDLE;
end
default: begin
state <= IDLE;
end
endcase
if (counter_rst) begin
counter <= 0;
tx_busy <= 1;
end else begin
counter <= counter + 1;
tx_busy <= 0;
end
end
end
endmodule
// 串口发送模块
module uart_tx(
input clk,
input rst_n,
input [3:0] data,
output reg busy
);
// 定义波特率常量
localparam BAUD_RATE = 9600;
// 定义计数器常量
localparam DATA_BITS = 8;
localparam STOP_BITS = 1;
localparam START_BITS = 1;
localparam COUNTER_MAX = BAUD_RATE / (DATA_BITS + STOP_BITS + START_BITS);
// 定义计数器和计数器复位信号
reg [15:0] counter = 16'd0;
wire counter_rst = (counter == COUNTER_MAX);
// 定义发送状态和发送数据
reg [3:0] state = 4'h0;
reg [7:0] tx_data = 8'h0;
// 定义发送时序
always @(posedge clk or negedge rst_n) begin
if (~rst_n) begin
state <= 4'h0;
tx_data <= 8'h0;
counter <= 0;
busy <= 0;
end else begin
case (state)
4'h0: begin
if (!busy) begin
tx_data <= 8'h0;
state <= 4'h1;
end
end
4'h1: begin
tx_data <= 8'hFF;
state <= 4'h2;
end
4'h2: begin
tx_data <= data;
state <= 4'h3;
end
4'h3: begin
tx_data <= 8'h00;
state <= 4'h0;
end
default: begin
state <= 4'h0;
end
endcase
if (counter_rst) begin
counter <= 0;
busy <= 1;
end else begin
counter <= counter + 1;
busy <= 0;
end
end
end
// 定义串口发送引脚
assign tx = !tx_data;
endmodule
```
注意:这只是一个简单的实现,具体的实现方式可能因不同的硬件平台和通信协议而异,需要根据具体情况进行调整。另外,为了方便起见,这里使用了一个简单的计数器来产生波特率,实际上,更好的实现方式是使用一个 PLL 或者专门的串口通信模块。