zedboard学习记录.1.纯PL流水灯

环境：vivado 217.4

开发板： zedboard ver.d xc7z020clg484-1

1.打开Vivado新建一个RTL工程。

2.add source->add/create design resouce->create ->finish

3.写入内容。

 1 module FlowingLamp(
 2    input    wire            GCLK,  //PL 100mhz
 3    input    wire            BTNU,  //low
 4    output   wire    [7:0]   LED  
 5    );  
 6 wire    clk_100m;   //clk 100mhz
 7 wire    rst;        //reset
 8 reg     clk_2hz;    //0.5s
 9 reg     [7:0]   led_reg;
10 reg     [31:0]  delay_cnt;
11 
12 assign LED      =   led_reg;
13 assign clk_100m =   GCLK;
14 assign rst      =   BTNU;
15 
16 //clk_2hz
17 always@(posedge clk_100m or negedge rst)
18 begin
19     if(rst)begin
20         clk_2hz   <= 1'b0;
21         delay_cnt <= 32'h0;
22     end
23     else begin
24         if(delay_cnt == 32'd25_000_000 - 32'd1)begin
25             delay_cnt <= 32'h0;
26             clk_2hz   <= ~clk_2hz;
27         end
28         else begin
29             delay_cnt <= delay_cnt + 1'b1;
30         end
31     end
32 end
33  
34  //led_reg
35 always @(posedge clk_2hz or posedge rst)
36  begin
37      if(rst)
38          led_reg <= 8'h01;
39      else
40          led_reg <= {led_reg[6:0],led_reg[7]};
41  end
42        
43 endmodule