一 信号

框图：

其中 key_filter seg_595_dynamic均为已有模块，直接例化即可使用，rom_8*256模块，调用rom ip实现。Rom_ctrl模块需要重新编写。

波形图：

二 代码

module key_fliter
#(parameter  CNT_MAX =24'd9_999_999
(input wire sys_clk,input wire sys_rst_n,input wire key1,input wire key2,output wire [7:0] addr
);reg [2:0] cnt_200ms;//定义中间变量。
reg       key1_en;
reg       key2_en;always@(posedge sys_clk or negedge sys_rst_n)if(sys_rst_n==1'b0)//异步复位。cnt_200ms<=24'd0;//赋初值。else   if(cnt_200ms ==CNT_MAX || key1_en ==1'b1 || key2_en == 1'b1)cnt_200ms<= 24'd0;//清零。else  cnt_200ms <= cnt_200ms + 1'b1；//计数。always@(posedge sys_clk or negedge sys_rst_n)if(sys_rst_n==1'b0)//异步复位。key1_en_<=1'b0;//赋初值。else      if(key2 == 1'b1)key1_en<=1'b0;//取低电平。else      if(key1 ==1'b1)key1_en<=~key1_en;//取反。else key1_en<=~key1_en;//保持。always@(posedge sys_clk or negedge sys_rst_n)if(sys_rst_n==1'b0)//异步复位。key2_en_<=1'b0;//赋初值。else      if(key1 == 1'b1)key2_en<=1'b0;//取低电平。else      if(key2 ==1'b1)key2_en<=~key2_en;//取反。else key2_en<=~key2_en;//保持。always@(posedge sys_clk or negedge sys_rst_n)if(sys_rst_n==1'b0)//异步复位。addr <= 8'd0;//赋初值。else      if(addr == 8'd255 && cnt_200ms ==CNT_MAX)addr <= 8'd0;else      if(key1 == 1'b1)addr <= 8'd99;else      if(key2 == 1'b1)addr <= 8'd199;else      if(cnt_200ms ==CNT_MAX)addr <= addr + 1'b1;endmodule

module  rom//工程顶层文件。
(input wire sys_clk,input wire key1,input wire sys_rst_n,input wire key2,output wire ds,output wire oe,output wire shcp,output wire stcp
);
wire key2_flag ;wire key1_flag ;
wire [7:0] addr ;
wire [7:0] data ;key_filter
#(.CNT_MAX (20'd9)
)
key_filter_inst1
(.sys_clk  (sys_clk),.sys_rst_n (sys_rst_n),.key_in (key1),.key_flag (key1_flag)
);//按键消抖模块实例化。key_filter
#(.CNT_MAX (20'd9)
)
key_filter_inst1
(.sys_clk  (sys_clk),.sys_rst_n (sys_rst_n),.key_in (key2),.key_flag (key2_flag)
);//按键消抖模块实例化。rom_ctrl_inst
(.sys_clk  (sys_clk),.sys_rst_n (sys_rst_n),.key1  (key1_flag),.key2  (key2_flag),.addr   (addr)
);//rom_ctrl模块实例化。rom_8x236 rom_8x236_inst
(.address (addr),.clock   (sys_clk),.q       (data)
);//rom ip核实例化。seg_595_dynamic  seg_595_dynamic
(.sys_clk  (sys_clk),.sys_rst_n (sys_rst_n),.data ({12'b0,data}),.point (6'b000_000),.sign  (1'b0),.seg_en (1'b1),.ds     (ds ),.oe     (oe ),.shcp   (shcp),);//数码管显示模块，实例化。

代码编译通过，对顶层文件进行仿真验证。

'timescale 1ns/1ns
module  tb_rom()reg  sys_clk;
reg  sys_rst_n;
reg  key1;
reg  key2;wire ds;
wire oe;
wire shcp;
wire stcp;initialbeginsys_clk =1'b1;sys_rst_n <= 1'b0;key1 <= 1'b1;key2 <= 1'b1;#20sys_rst_n <= 1'b1;#700000
//key1key1 <= 1'b0;#20key1 <= 1'b1;#20key1 <= 1'b0;#20key1 <= 1'b1;#20key1 <= 1'b0;#20key1 <= 1'b1;#20key1 <= 1'b0;#20key1 <= 1'b1;#20key1 <= 1'b0;#20key1 <= 1'b0;
//key2#20000key2 <= 1'b0;#20key2 <= 1'b1;#20key2 <= 1'b0;#20key2 <= 1'b1;#20key2 <= 1'b0;#200key2 <= 1'b1;#20key2 <= 1'b0;#20key2 <= 1'b1;#20key2 <= 1'b0;#20key2 <= 1'b0;endalways #10 sys_clk = ~sys_clk;rom rom_inst
(.sys_clk    (sys_clk),.sys_rst_n  (sys_rst_n),.key1       (key1),.key2       (key2),.ds         (ds),.oe         (oe),.shcp       (shcp),.stcp       (stcp)
);