esp8266与串口连接的verilog代码

下面是一个简单的Verilog代码，用于将ESP8266与串口连接：

module esp8266_uart(
    input clk,
    input rst,
    input [7:0] uart_rx,
    output [7:0] uart_tx,
    output esp8266_rst,
    output esp8266_en,
    output esp8266_tx,
    output esp8266_rx
    );

    reg [7:0] uart_tx_reg;
    reg [31:0] rx_data;
    reg [3:0] rx_state;
    reg [31:0] tx_data;
    reg [3:0] tx_state;
    reg esp8266_rst_reg;
    reg esp8266_en_reg;
    reg esp8266_tx_reg;
    wire esp8266_rx_wire;

    assign esp8266_rx = esp8266_rx_wire;

    // UART Receive State Machine
    always @(posedge clk) begin
        if (rst) begin
            rx_state <= 4'b0000;
            rx_data <= 0;
        end else begin
            case (rx_state)
                4'b0000: begin // IDLE
                    if (~uart_rx[0]) begin
                        rx_state <= 4'b0001;
                    end
                end
                4'b0001: begin // START
                    rx_state <= 4'b0010;
                end
                4'b0010: begin // DATA
                    rx_data <= {rx_data[23:0], uart_rx};
                    rx_state <= 4'b0011;
                end
                4'b0011: begin // PARITY
                    rx_state <= 4'b0100;
                end
                4'b0100: begin // STOP
                    if (uart_rx[0]) begin
                        // Data has been received successfully
                        // Check if it's an ESP8266 command
                        if (rx_data == 32'h52534c42) begin // "RSLB" command received
                            esp8266_rst_reg <= 1;
                        end else if (rx_data == 32'h454e424c) begin // "ENBL" command received
                            esp8266_en_reg <= 1;
                        end else if (rx_data == 32'h54584c42) begin // "TXLB" command received
                            esp8266_tx_reg <= 1;
                        end else begin
                            // Pass the received data to the transmit state machine
                            tx_data <= rx_data;
                            tx_state <= 4'b0001;
                        end
                    end
                    rx_state <= 4'b0000;
                end
            endcase
        end
    end

    // UART Transmit State Machine
    always @(posedge clk) begin
        if (rst) begin
            uart_tx_reg <= 8'h00;
            tx_state <= 4'b0000;
        end else begin
            case (tx_state)
                4'b0000: begin // IDLE
                    if (esp8266_tx_reg) begin
                        tx_state <= 4'b0001;
                    end
                end
                4'b0001: begin // START
                    uart_tx_reg <= 8'hFF;
                    tx_state <= 4'b0010;
                end
                4'b0010: begin // DATA
                    uart_tx_reg <= tx_data[31:24];
                    tx_data <= {tx_data[23:0], 0};
                    tx_state <= 4'b0011;
                end
                4'b0011: begin // PARITY
                    uart_tx_reg <= 8'h00;
                    tx_state <= 4'b0100;
                end
                4'b0100: begin // STOP
                    uart_tx_reg <= 8'hFF;
                    tx_state <= 4'b0000;
                    esp8266_tx_reg <= 0;
                end
            endcase
        end
    end

    // ESP8266 Reset and Enable
    always @(posedge clk) begin
        if (rst) begin
            esp8266_rst_reg <= 0;
            esp8266_en_reg <= 0;
        end else begin
            if (esp8266_en_reg) begin
                esp8266_en_reg <= 0;
            end
            if (esp8266_rst_reg) begin
                esp8266_rst_reg <= 0;
            end
        end
    end

    // Connect the UART
    assign uart_tx = uart_tx_reg;
    assign esp8266_rx_wire = uart_rx;

    // Connect the ESP8266
    assign esp8266_rst = esp8266_rst_reg;
    assign esp8266_en = esp8266_en_reg;
    assign esp8266_tx = esp8266_tx_reg;

endmodule

在这个代码中，我们使用了两个状态机：一个用于接收UART数据，一个用于发送UART数据。此外，我们还添加了一些逻辑，用于处理ESP8266的重置和启用。请注意，这只是一个简单的示例代码，您需要根据您的具体需求进行修改。