用vivado设计用于FPGA板的代码，实现多种形式的流水灯（LD0~LD7）。可用6个开关切换模式。（灯的闪烁周期均为1秒） （1）按键1按下后灯从左到右按顺序轮流闪1次，循环执行； （2）按键2按下后所有灯闪烁3次； （3）按键3按下后灯从右到左按顺序轮流闪烁1次，循环执行； （4）按键4按下后奇数灯和偶数灯轮流各闪3次，； （5）按键5按下后前4盏灯从右到左闪一遍； （6）按键6按下后后4盏灯从左到右闪一遍。

以下是基于Vivado的FPGA实现代码，实现多种形式的流水灯：

module led_controller(
    input clk,        // 时钟信号
    input [5:0] sw,   // 6个开关输入信号
    output reg [7:0] leds   // 8个LED灯输出信号
);

reg [7:0] led_pattern;  // LED灯的模式
reg [2:0] mode;         // 当前模式
reg [2:0] count;        // 闪烁计数器

// 模式1：按键1按下后灯从左到右按顺序轮流闪1次，循环执行
reg [2:0] index1;       // 灯的位置
always @ (posedge clk) begin
    if (sw[0]) begin
        mode <= 3'b001;
        count <= 0;
        index1 <= 3'b000;
    end else if (mode == 3'b001) begin
        if (count == 3'd0) begin
            led_pattern <= {led_pattern[6:0], led_pattern[7]};
            if (index1 == 3'b111) index1 <= 3'b000;
            else index1 <= index1 + 3'd1;
            count <= 3'd1;
        end else begin
            count <= count + 3'd1;
        end
    end
end

// 模式2：按键2按下后所有灯闪烁3次
always @ (posedge clk) begin
    if (sw[1]) begin
        mode <= 3'b010;
        count <= 0;
    end else if (mode == 3'b010) begin
        if (count == 3'd0) begin
            led_pattern <= ~led_pattern;
            count <= 3'd1;
        end else if (count == 3'd3) begin
            led_pattern <= 8'h00;
            count <= 3'd0;
        end else begin
            count <= count + 3'd1;
        end
    end
end

// 模式3：按键3按下后灯从右到左按顺序轮流闪烁1次，循环执行
reg [2:0] index3;       // 灯的位置
always @ (posedge clk) begin
    if (sw[2]) begin
        mode <= 3'b011;
        count <= 0;
        index3 <= 3'b111;
    end else if (mode == 3'b011) begin
        if (count == 3'd0) begin
            led_pattern <= {led_pattern[0], led_pattern[7:1]};
            if (index3 == 3'b000) index3 <= 3'b111;
            else index3 <= index3 - 3'd1;
            count <= 3'd1;
        end else begin
            count <= count + 3'd1;
        end
    end
end

// 模式4：按键4按下后奇数灯和偶数灯轮流各闪3次
reg [2:0] index4;       // 灯的位置
always @ (posedge clk) begin
    if (sw[3]) begin
        mode <= 3'b100;
        count <= 0;
        index4 <= 3'b000;
    end else if (mode == 3'b100) begin
        if (count == 3'd0) begin
            if (index4[0]) led_pattern[index4] <= 1'b0;
            else led_pattern[index4] <= 1'b1;
            if (index4 == 3'b111) index4 <= 3'b000;
            else index4 <= index4 + 3'd1;
            count <= 3'd1;
        end else if (count == 3'd3) begin
            count <= 3'd0;
        end else begin
            count <= count + 3'd1;
        end
    end
end

// 模式5：按键5按下后前4盏灯从右到左闪一遍
reg [2:0] index5;       // 灯的位置
always @ (posedge clk) begin
    if (sw[4]) begin
        mode <= 3'b101;
        count <= 0;
        index5 <= 3'b100;
    end else if (mode == 3'b101) begin
        if (count == 3'd0) begin
            led_pattern[index5] <= 1'b1;
            if (index5 == 3'b000) begin
                count <= 3'd4;
            end else begin
                index5 <= index5 - 3'd1;
                count <= 3'd1;
            end
        end else if (count == 3'd4) begin
            led_pattern <= 8'h00;
            count <= 3'd0;
        end else begin
            count <= count + 3'd1;
        end
    end
end

// 模式6：按键6按下后后4盏灯从左到右闪一遍
reg [2:0] index6;       // 灯的位置
always @ (posedge clk) begin
    if (sw[5]) begin
        mode <= 3'b110;
        count <= 0;
        index6 <= 3'b011;
    end else if (mode == 3'b110) begin
        if (count == 3'd0) begin
            led_pattern[index6] <= 1'b1;
            if (index6 == 3'b111) begin
                count <= 3'd4;
            end else begin
                index6 <= index6 + 3'd1;
                count <= 3'd1;
            end
        end else if (count == 3'd4) begin
            led_pattern <= 8'h00;
            count <= 3'd0;
        end else begin
            count <= count + 3'd1;
        end
    end
end

assign leds = led_pattern;

endmodule

该代码实现了六种不同的模式，使用六个开关作为模式选择输入。在不同的模式下，LED灯的输出会发生变化，实现不同的流水灯效果。