lin协议 主机任务状态机verilog代码

以下是一个简单的基于 Lin 2.0 协议的主机任务状态机的 Verilog 代码示例：

module lin_master_task_state_machine(
    input clk,
    input reset,
    input tx_en,
    input rx_en,
    input tx_data,
    output reg tx_ready,
    output reg tx_break,
    output reg[7:0] rx_data,
    output reg rx_complete,
    output reg rx_error
);

// LIN 2.0 protocol states
typedef enum {
    IDLE,
    BREAK,
    SYNCH,
    HEADER,
    DATA,
    CHECKSUM
} lin_state_t;

// Task state machine states
typedef enum {
    INIT,
    TX,
    RX
} task_state_t;

// Variables to hold task state machine state and LIN protocol state
reg[1:0] task_state;
reg[2:0] lin_state;

// Variables to hold header and data bytes
reg[5:0] header;
reg[7:0] data[8];

// Variables to hold checksum and checksum validation
reg[7:0] checksum;
reg[1:0] checksum_state;

// Constants for break and sync intervals
parameter BREAK_TIME = 104;
parameter SYNC_TIME = 13;

// Counter for break and sync intervals
reg[6:0] counter;

// Initialize task state machine and LIN protocol state
initial begin
    task_state = INIT;
    lin_state = IDLE;
end

// Main state machine
always @(posedge clk) begin
    if (reset) begin
        task_state <= INIT;
        lin_state <= IDLE;
        tx_ready <= 1'b0;
        tx_break <= 1'b0;
        rx_data <= 8'd0;
        rx_complete <= 1'b0;
        rx_error <= 1'b0;
        counter <= 7'd0;
    end
    else begin
        case (task_state)
            INIT:
                if (tx_en) begin
                    task_state <= TX;
                    lin_state <= BREAK;
                    tx_ready <= 1'b1;
                    tx_break <= 1'b1;
                    counter <= BREAK_TIME;
                end
                else if (rx_en) begin
                    task_state <= RX;
                    lin_state <= IDLE;
                end
            TX:
                case (lin_state)
                    BREAK:
                        if (counter == 7'd0) begin
                            lin_state <= SYNCH;
                            tx_break <= 1'b0;
                            counter <= SYNC_TIME;
                        end
                        else begin
                            counter <= counter - 1'd1;
                        end
                    SYNCH:
                        if (counter == 7'd0) begin
                            lin_state <= HEADER;
                            header <= 6'b100000;
                            counter <= 7'd5;
                        end
                        else begin
                            counter <= counter - 1'd1;
                        end
                    HEADER:
                        if (counter == 7'd0) begin
                            lin_state <= DATA;
                            data[0] <= tx_data;
                            counter <= 7'd8;
                        end
                        else begin
                            counter <= counter - 1'd1;
                        end
                    DATA:
                        if (counter == 7'd0) begin
                            if (checksum_state == 2'd0) begin
                                lin_state <= CHECKSUM;
                                checksum <= header + tx_data;
                                for (int i = 0; i < 8; i = i + 1) begin
                                    checksum <= checksum + data[i];
                                end
                                checksum_state <= 2'd1;
                                counter <= 7'd8;
                            end
                            else begin
                                lin_state <= IDLE;
                                tx_ready <= 1'b0;
                                task_state <= INIT;
                            end
                        end
                        else begin
                            data[counter-1] <= tx_data;
                            counter <= counter - 1'd1;
                        end
                    CHECKSUM:
                        if (counter == 7'd0) begin
                            if (checksum_state == 2'd1) begin
                                lin_state <= IDLE;
                                tx_ready <= 1'b0;
                                task_state <= INIT;
                            end
                            else begin
                                rx_complete <= 1'b1;
                                counter <= 7'd8;
                            end
                        end
                        else begin
                            checksum <= checksum + rx_data;
                            counter <= counter - 1'd1;
                        end
                endcase
            RX:
                case (lin_state)
                    IDLE:
                        if (rx_en) begin
                            lin_state <= BREAK;
                            rx_complete <= 1'b0;
                            rx_error <= 1'b0;
                            counter <= BREAK_TIME;
                        end
                    BREAK:
                        if (rx_en) begin
                            if (counter == 7'd0) begin
                                lin_state <= SYNCH;
                                counter <= SYNC_TIME;
                            end
                            else begin
                                counter <= counter - 1'd1;
                            end
                        end
                        else begin
                            lin_state <= IDLE;
                            rx_error <= 1'b1;
                            task_state <= INIT;
                        end
                    SYNCH:
                        if (rx_en) begin
                            if (counter == 7'd0) begin
                                lin_state <= HEADER;
                                header <= rx_data;
                                checksum <= header;
                                checksum_state <= 2'd1;
                                counter <= 7'd5;
                            end
                            else begin
                                counter <= counter - 1'd1;
                            end
                        end
                        else begin
                            lin_state <= IDLE;
                            rx_error <= 1'b1;
                            task_state <= INIT;
                        end
                    HEADER:
                        if (rx_en) begin
                            if (counter == 7'd0) begin
                                lin_state <= DATA;
                                data[0] <= rx_data;
                                checksum <= checksum + rx_data;
                                counter <= 7'd8;
                            end
                            else begin
                                counter <= counter - 1'd1;
                            end
                        end
                        else begin
                            lin_state <= IDLE;
                            rx_error <= 1'b1;
                            task_state <= INIT;
                        end
                    DATA:
                        if (rx_en) begin
                            if (counter == 7'd0) begin
                                if (checksum_state == 2'd1) begin
                                    lin_state <= CHECKSUM;
                                    checksum <= checksum + rx_data;
                                    checksum_state <= 2'd2;
                                    counter <= 7'd8;
                                end
                                else begin
                                    lin_state <= IDLE;
                                    rx_error <= 1'b1;
                                    task_state <= INIT;
                                end
                            end
                            else begin
                                data[counter-1] <= rx_data;
                                checksum <= checksum + rx_data;
                                counter <= counter - 1'd1;
                            end
                        end
                        else begin
                            lin_state <= IDLE;
                            rx_error <= 1'b1;
                            task_state <= INIT;
                        end
                    CHECKSUM:
                        if (rx_en) begin
                            if (counter == 7'd0) begin
                                if (checksum_state == 2'd2 && checksum == 8'd0) begin
                                    rx_complete <= 1'b1;
                                    lin_state <= IDLE;
                                    task_state <= INIT;
                                end
                                else begin
                                    lin_state <= IDLE;
                                    rx_error <= 1'b1;
                                    task_state <= INIT;
                                end
                            end
                            else begin
                                checksum <= checksum + rx_data;
                                counter <= counter - 1'd1;
                            end
                        end
                        else begin
                            lin_state <= IDLE;
                            rx_error <= 1'b1;
                            task_state <= INIT;
                        end
                endcase
        endcase
    end
end

endmodule

请注意，此代码是一个简单示例，并且可能需要根据您的应用程序进行修改和调整。此外，此代码只实现了协议的发送和接收部分，您还需要添加适当的硬件接口和控制逻辑以与您的特定系统集成。