VerilogRS232串口通信控制电路设计
时间: 2023-07-31 21:13:42 浏览: 44
为了实现VerilogRS232串口通信控制电路,需要使用FPGA或者CPLD进行设计。下面是一个简单的Verilog代码,可以实现RS232的发送和接收功能。其中,CLK为时钟信号,RST为复位信号,TXD为发送数据输出端口,RXD为接收数据输入端口,BAUDRATE为波特率。
```
module RS232(
input CLK,
input RST,
output reg TXD,
input RXD,
parameter BAUDRATE = 9600
);
reg [7:0] tx_data;
reg [3:0] tx_count;
reg [3:0] rx_count;
reg [7:0] rx_data;
reg start_bit;
reg stop_bit;
reg tx_busy;
wire rx_valid;
assign rx_valid = (start_bit && !stop_bit);
// 时钟分频
reg [15:0] baud_count;
always @(posedge CLK or posedge RST) begin
if(RST) begin
baud_count <= 0;
tx_count <= 0;
tx_busy <= 0;
tx_data <= 0;
start_bit <= 0;
stop_bit <= 1;
rx_count <= 0;
rx_data <= 0;
end else begin
baud_count <= baud_count + 1;
if(baud_count >= BAUDRATE) begin
baud_count <= 0;
if(tx_busy) begin
if(tx_count == 0) begin
tx_busy <= 0;
end else begin
tx_count <= tx_count - 1;
end
end
if(rx_count < 8) begin
rx_count <= rx_count + 1;
rx_data <= {rx_data[6:0], RXD};
if(rx_count == 1) begin
start_bit <= 1;
end else if(rx_count == 9) begin
stop_bit <= 0;
end
end else begin
start_bit <= 0;
if(rx_valid) begin
// 处理接收数据
end
rx_count <= 0;
stop_bit <= 1;
end
end
end
end
// 发送数据
always @(posedge CLK or posedge RST) begin
if(RST) begin
tx_count <= 0;
tx_busy <= 0;
tx_data <= 0;
TXD <= 1;
end else begin
if(!tx_busy && tx_count == 0) begin
tx_data <= // 获取需要发送的数据
tx_count <= 10;
tx_busy <= 1;
TXD <= 0;
end else if(tx_busy) begin
if(tx_count == 0) begin
tx_busy <= 0;
TXD <= 1;
end else begin
tx_count <= tx_count - 1;
TXD <= tx_data[0];
tx_data <= {tx_data[6:0], 1};
end
end
end
end
endmodule
```
以上代码仅供参考,具体实现需要根据实际需要进行修改。同时,还需要根据具体的FPGA或CPLD器件进行引脚和时钟等设置。