Verilog程序例子
Verilog程序代码集
1.全加器Sum=A⊕B⊕CinCount=AB+Cin（A+B）①数据流module adder(a,b,Cin,Sum,Count); input [2:0]a,b;input Cin;output [2:0] Sum;output Count;assign {Count,Sum}=a+b+Cin; endmodule②行为描述always语句module adder(a,b,c,Cin,Sum,Count); input [4:0] a,b;input Cin;output reg [4:0] Sum;output reg Count;reg T1,T2,T3;always@(a or b or Cin)beginSum=a^b^Cin;T1=A&B;T2=Cin&A;T3=Cin&B;Count=T1|T2|T3;endendmodule③结构体module adder （a,b,Cin,Sum,Count）；input a,b,Cin;output Sum,Count;Xor a1(s1,a1,b);Xor a2(Sum,s1,Cin);and a3(T1,a,b);or a4(T2,a,b);and a5(T3,Cin,T2);or a6(Count,T1,T3);Endmodule2.数值比较器①判断两值是否相等module compare(a,b,equal);input [7:0] a,b;output equal;assign equal=(a==b)?|0; ②谁大谁输出module compare(a,b,out);input [7:0] a,b;output reg[7:0] out;always@(a or b)beginif (a>b) out<=a;else if (a==b) out<=a;else out<=b;endendmodule③输出参数module compare(a.b.xgy,xsy,xey);input [7:0] x,y;output reg xgy,xsy,xey;always@(x or y)beginif (x==y) xey=1;else xey=0;if (x>y) begin xgy=1;xsy=0;endelse if (x<y) begin xgy=0;xsy=1;end endendmodule3.编码器（4-2 8-3 16-4编码）①case语句8-3编码（优先）module code （in ，out）；input [7:0] in;output reg [2:0] out;always@(in)case x(in)begin f=1;8’b1xxxxxxx:out=3’b111;end begin f=1;8’b01xxxxxx:out=3’b110;end begin f=1;8’b001xxxxx:out=3’b101;end begin f=1;8’b0001xxxx:out=3’b100;end begin f=1;8’b00001xxx:out=3’b011;end begin f=1;8’bxx:out=3’b010;endbegin f=1;8’bx:out=3’b001;endbegin f=1;8’b:out=3’b000;end default:begin f=0:out=3’b000;end endcaseendmodule②if-else语句（4-2优先编码）module code(in,out);input[3:0] in;output reg [1:0] out;always@(in)if (in[3]==1):begin f=1;out=2’b11;end else if (in[2]==1):begin f=1;out=2’b10;end else if (in[1]==1):begin f=1;out=2’b01;end else if (in[0]==1):begin f=1;out=2’b00;end else begin f=0;out=2’b00;end endmodule4.多路选择器①行为描述（4选1）module choice(A,B,C,D,ncs addr out);input [7:0]A,B,C,D;input ncs;input [1:0] addr ;output reg[7:0] out;always@(A or B or C or D or ncs or addr) beginif (!ncs)case(addr)2’b00:out=A;2’b01:out=B;2’b10:out=C;2’b11:out=D;endcaseelse out=0;endendmodule5.设计一个4位双向移位寄存器。
veriloghdl程序大全
1.简单门电路的设计二输入与非门module nand_2(y,a,b);output y;input a,b;nand(y,a,b);endmodule二输入异或门module nand_2(y,a,b);output y;input a,b;reg y;always @(a,b)begincase({a,b})2’b00:y=1;2’b01:y=1;2’b10:y=1;2’b11:y=0;default:y=’bx;endcaseendendmodule二输入三态门module eda_santai(dout,din,en); output dout;input din,en;reg dout;alwaysif (en) dout<=din;else dout<=’bz;endmodule3-8译码器的设计module yimaqi(S1,S2,S3,A,Y); input S1;wire S1;input S2;wire S2;input S3;wire S3;input [2:0]A;wire [2:0]A;output[7:0]Y;reg [7:0]Y;reg s;always@(S,S1,S2,S3)begins<=S2|S3;Y <=8'b1111_1111;else if(S)Y <=8'b1111_1111;elsecase(A)3'b000:Y<=11111110;3'b001:Y<=11111101;3'b010:Y<=11111011;3'b011:Y<=11110111;3'b100:Y<=11101111;3'b101:Y<=11011111;3'b110:Y<=10111111;3'b111:Y<=01111111;endcaseendendmodule2.8-3编码器的设计module banjiaqi(a,b,count,sum);input a;wire a;input b;wire b;output count;wire count;output sum;wire sum;assign {count,sum}=a+b;endmodule4. D触发器的设计module Dchufaqi ( Q ,CLK ,RESET ,SET ,D ,Qn ); input CLK ;wire CLK ;input RESET ;wire RESET ;input SET ;wire SET ;input D ;wire D ;output Q ;reg Q ;output Qn ;wire Qn ;assign Qn = ~Q ;always @ ( posedge CLK or negedge SET or negedge RESET ) beginif ( !RESET)Q <= 0 ;else if ( ! SET)Q <= 1;else Q <= D;endendmodule5. 1位半加法器的设计module banjiafaqi(a,b,sum,count);input a;wire a;input b;wire b;output sum;wire sum;output count;wire count;assign {count,sum}=a+b;endmodule6. 4位计数器的设计module sihisjishuqi(CLK,RESET,out);input CLK;wire CLK;input RESET;wire RESET;output[3:0] out;reg[3:0] out;always @ ( posedge CLK or negedge RESET )beginif(!RESET)out<=4'b0000;elsebeginout<=out+1;if(out==4'b1010)out<=4'b0000;endendendmodule7.分频时序逻辑电路的设计module eda_fp_even(clk_out,clk_in,rst); input clk_in;input rst;wire rst;output clk_out;reg clk_out;reg [1:0]cnt;parameter N=6;always @(posedge clk_in or negedge rst) beginif(!rst)beginclk_out<=0;cnt<=0;endelsebegincnt<=cnt+1;if(cnt==N/2-1)beginclk_out=!clk_out;cnt<=0;endendendendmodule8.7段显示译码器的设计module eda_scan_seven(clk,dig,y,rst); input clk;wire clk;input rst;wire rst;output[7:0] dig;wire[7:0] dig;output [7:0]y;wire [7:0]y;reg clkout;reg [19:0]cnt;reg [2:0]wei;reg [3:0]duan;reg [6:0]Y_r;reg [7:0]dig_r;assign y = {1'b1,(~Y_r[6:0])};assign dig =~dig_r;parameter period= 1000000;always@(posedge clk or negedge rst) beginif(!rst)cnt<=0;else begincnt<=cnt+1;if(cnt==(period>>1)-1)clkout<=#1 1'b1;else if(cnt==period-1)beginclkout<=#1 1'b0;cnt<=#1 1'b0;endendendalways@(posedge clkout or negedge rst ) beginif(!rst)wei<=0;elsewei<=wei+1;endalways @(wei) //数码管选择begincase ( wei )3'b000 :begindig_r <= 8'b0000_0001;duan <= 1;end3'b001 :begindig_r <= 8'b0000_0010;duan<= 3;end3'b010 :begindig_r <= 8'b0000_0100;duan<= 5;end3'b011 :begindig_r <= 8'b0000_1000;duan <= 7;end3'b100 :begindig_r <= 8'b0001_0000;duan<= 9;end3'b101 :begindig_r <= 8'b0010_0000;duan<= 11;end3'b110 :begindig_r <= 8'b0100_0000;duan <= 13;end3'b111 :begindig_r <= 8'b1000_0000;duan<= 15;endendcaseendalways @ ( duan ) //译码begincase ( duan )0: Y_r = 7'b0111111; // 01: Y_r = 7'b0000110; // 12: Y_r = 7'b1011011; // 23: Y_r = 7'b1001111; // 34: Y_r = 7'b1100110; // 45: Y_r = 7'b1101101; // 56: Y_r = 7'b1111101; // 67: Y_r = 7'b0100111; // 78: Y_r = 7'b1111111; // 89: Y_r = 7'b1100111; // 910: Y_r = 7'b1110111; // A11: Y_r = 7'b1111100; // b12: Y_r = 7'b0111001; // c13: Y_r = 7'b1011110; // d14: Y_r = 7'b1111001; // E15: Y_r = 7'b1110001; // Fdefault: Y_r = 7'b0000000;endcaseendendmodule9.数据选择器的设计module eda_8xuanyi (A,D0,D1,D2,D3,D4,D5,D6,D7,G,Y); input D0,D1,D2,D3,D4,D5,D6,D7,G;input [2:0]A;wire [2:0]A;output Y;reg Y;always @(A, G)beginif (G==0)Y<=0;elsecase(A)3'b000:Y=D0;3'b001:Y=D1;3'b010:Y=D2;3'b011:Y=D3;3'b100:Y=D4;3'b101:Y=D5;3'b110:Y=D6;3'b111:Y=D7;endcaseendendmodule10.数据锁存器的设计module e da_suocunqi(q,d,oen,g); output[7:0] q;//数据输出端input[7:0] d;//数据输入端input oen,g;//三态控制端reg[7:0] q;always @(*)beginif (oen)beginq<="z";endelsebeginif(g)q<=d;elseq<=q;endendendmodule11.数据寄存器的设计module eda_jicunqi(r,clk,d,y); input r,clk;input [7:0]d;wire [7:0]d;output [7:0]y;reg [7:0]y;always @ (posedge clk or negedge r) beginif(!r)y<=8'b00000000;elsey<=d;endendmodule12.顺序脉冲发生器的设计module eda_shunxu(clk,clr,q);input clk,clr;output [7:0]q;reg [7:0]q;always @ ( posedge clk or posedge clr ) beginif ( clr==1)beginq<=8'b00000000; //赋初值endelsebeginif(q==0)q<=8'b00000001;elseq<=q<<1; //给初值进行移位endendendmodule13.1位全加法器的设计module quanjiaqi(a,b,sum,count,cin); input a;wire a;input b;wire b;input cin;wire cin;output sum;wire sum;output count;wire count;assign{sum,count}=a+b+cin; endmodule15.键控Led灯的设计module eda_led(led,key);input key;output led;reg led_out;assign led<=led_out;always@(key)beginif(key)led_out<=1;else if(!key)led_out<=0;endendmodule16．双向移位寄存器的设计module eda_yiweijicunqi( left_right ,load ,clr ,clk ,DIN ,DOUT );input left_right ;wire left_right ;input load ;wire load ;input clr ;wire clr ;input clk ;wire clk ;input [3:0] DIN ;wire [3:0] DIN ;output [3:0] DOUT ;wire [3:0] DOUT ;reg [3:0] data_r;assign DOUT = data_r ;always @ (posedge clk or posedge clr or posedge load)//敏感变量，看真值表beginif(clr==1)data_r <= 0;//判断是否清零else if (load )data_r<=DIN;//判断是否装载数据//判断进行左移位还是右移位elsebeginif(left_right)data_r<=DIN<<1;elsedata_r<=DIN>>1;endendendmodule17.8-3优先编码器的设计module youxianbianma( A ,I ,GS ,EO ,EI ); input [7:0] I ;wire [7:0] I ;input EI ;wire EI ;output [2:0] A ;reg [2:0] A ;output GS ;reg GS ;output EO ;reg EO ;always @ ( I or EI )if ( EI )beginA <= 3'b111;GS <= 1;EO <= 1;endelse if (I==8'b11111111)beginA <= 3'b111;GS <= 1;EO <= 0;endelse if ( I==8'b11111110 )beginA <= 3'b111;GS <= 0;EO <= 1;endelse if ( I==8'b1111110x )beginA <= 3'b110;GS <= 0;EO <= 1;endelse if ( I==8'b111110xx )beginA <= 3'b101;GS <= 0;EO <= 1;endelse if ( I==8'b11110xxx )beginA <= 3'b100;GS <= 0;EO <= 1;endelse if ( I==8'b1110xxxx )beginA <= 3'b011;GS <= 0;EO <= 1;endelse if ( I==8'b110xxxxx )beginA <= 3'b010;GS <= 0;EO <= 1;endelse if ( I==8'b10xxxxxx )beginA <= 3'b001;GS <= 0;EO <= 1;endelse if ( I==8'b0xxxxxxx )beginA <= 3'b000;GS <= 0;EO <= 1;endendmodule18.数据分配器的设计module shujufenpeiqi(y0,y1,y2,y3,din,a); output y0,y1,y2,y3;//4??êy?Yí¨μàinput din;//êy?Yê?è?input [1:0] a;reg y0,y1,y2,y3;always @(din,a)beginy0=0;y1=0;y2=0;y3=0; //3?ê??ˉ￡á?case(a)00:y0=din;01:y1=din;02:y2=din;03:y3=din;endcase end endmodule。
Verilog的135个经典设计实例
Verilog的135个经典设计实例1、立即数放大器：立即数放大器是一种用于将输入电平放大到更高电平的电路，它可以实现任意输入到输出的映射，并且可以在Verilog中使用。
立即数放大器的Verilog实现如下：module immedamp(in, out);input in;output out;reg [3:0] immed;assign out = immed[3];begincase (in)4'b0000: immed = 4'b1000;4'b0001: immed = 4'b1001;4'b0010: immed = 4'b1010;4'b0011: immed = 4'b1011;4'b0100: immed = 4'b1100;4'b0101: immed = 4'b1101;4'b0110: immed = 4'b1110;4'b0111: immed = 4'b1111;4'b1000: immed = 4'b1000;4'b1001: immed = 4'b1001;4'b1010: immed = 4'b1010;4'b1011: immed = 4'b1011;4'b1100: immed = 4'b1100;4'b1101: immed = 4'b1101;4'b1110: immed = 4'b1110;4'b1111: immed = 4'b1111;endcaseendendmodule2、多路复用器：多路复用器是一种用于将多个输入选择转换为单个输出的电路，它可以实现由多种方式选择的输出，并可以使用Verilog实现。
verilog hdl语言100例详解
verilog hdl语言100例详解Verilog HDL语言是一种硬件描述语言，用于描述数字电路和系统的行为和结构。
它是硬件设计工程师在数字电路设计中的重要工具。
本文将介绍100个例子，详细解释Verilog HDL语言的应用。
1. 基本门电路：Verilog HDL可以用于描述基本门电路，如与门、或门、非门等。
例如，下面是一个描述与门电路的Verilog HDL代码：```verilogmodule and_gate(input a, input b, output y);assign y = a & b;endmodule```2. 多路选择器：Verilog HDL也可以用于描述多路选择器。
例如，下面是一个描述2:1多路选择器的Verilog HDL代码：```verilogmodule mux_2to1(input a, input b, input sel, output y);assign y = sel ? b : a;endmodule```3. 寄存器：Verilog HDL可以用于描述寄存器。
例如，下面是一个描述8位寄存器的Verilog HDL代码：```verilogmodule register_8bit(input [7:0] d, input clk, input reset, output reg [7:0] q);always @(posedge clk or posedge reset)if (reset)q <= 0;elseq <= d;endmodule```4. 计数器：Verilog HDL可以用于描述计数器。
例如，下面是一个描述8位计数器的Verilog HDL代码：```verilogmodule counter_8bit(input clk, input reset, output reg [7:0] count);always @(posedge clk or posedge reset)if (reset)count <= 0;elsecount <= count + 1;endmodule```5. 加法器：Verilog HDL可以用于描述加法器。
verilog的15个经典设计实例
begin b=a; c=b; end endmodule
【例 5.11】模为 60 的 BCD 码加法计数器
module count60(qout,cout,data,load,cin,reset,clk);
【例 5.6】用 fork-join 并行块产生信号波形
`timescale 10ns/1ns module wave2; reg wave; parameter cycle=5; initial
fork wave=0;
#(cycle) wave=1; #(2*cycle) wave=0; #(3*cycle) wave=1; #(4*cycle) wave=0; #(5*cycle) wave=1; #(6*cycle) $finish; join initial $monitor($time,,,"wave=%b",wave); endmodule
else
out<=out+1;
end
endmodule
//同步复位 //计数
【例 3.3】4 位全加器的仿真程序
`timescale 1ns/1ns `include "adder4.v" module adder_tp; reg[3:0] a,b; reg cin; wire[3:0] sum; wire cout; integer i,j;
output[7:0] qout;
output cout;
input[7:0] data;
input load,cin,clk,reset;
Verilog写的按键消抖程序
前几天看了特权同学用Verilog写的按键消抖程序，感觉很经典。
在这里将程序贴出来分享一下。
module lcd_button2(clk,rst,seg,wei,sw1,sw2,sw3,sw4);//按键按下,数码管依次显示0-9input clk;input rst;input sw1,sw2,sw3,sw4;output [3:0] wei;output[7:0] seg;reg [7:0] seg;reg [3:0] wei;integer num;initial beginnum = 0;endreg[3:0] key_rst;always @(posedge clk or negedge rst)if(!rst)key_rst <= 4'b1111;elsekey_rst <= {sw4,sw3,sw2,sw1};reg[3:0] key_rst_r;always @(posedge clk or negedge rst)if(!rst)key_rst_r <= 4'b111;elsekey_rst_r <= key_rst;wire[3:0] key_an = key_rst_r & (~key_rst);reg[19:0] cnt;always @(posedge clk or negedge rst)if(!rst)cnt <= 0;else if(key_an) cnt <= 0;else cnt <= cnt+1'b1;reg [3:0] low_sw;always @(posedge clk or negedge rst)if(!rst)low_sw <= 4'b1111;else if(cnt==10'hfffff)low_sw <= {sw4,sw3,sw2,sw1};reg[3:0] low_sw_r;always @(posedge clk or negedge rst)if(!rst)low_sw_r <= 4'b1111;elselow_sw_r <= low_sw;wire [3:0] led_ctrl = low_sw_r[3:0] & (~low_sw[3:0]);reg d1,d2,d3,d4;always @(posedge clk or negedge rst)if(!rst) begind1 <= 0;d2 <= 0;d3 <= 0;d4 <= 0;endelse beginif(led_ctrl[0]) beginnum <= num+1;if(num==9)num <= 0;endendalways @(posedge clk ) beginwei <= 4'b1111;case(num)0: seg <= 8'hfc;1: seg <= 8'h60;2: seg <= 8'hda;3: seg <= 8'hf2;4: seg <= 8'h66;5: seg <= 8'hb6;6: seg <= 8'hbe;7: seg <= 8'he0;8: seg <= 8'hfe;9: seg <= 8'hf6;default: seg <= 8'h02;endcaseendendmodule参考了特权的代码。
Verilog的150个经典设计实例
module adder4(cout,sum,ina,inb,cin);output[3:0] sum;output cout;input[3:0] ina,inb;input cin;assign {cout,sum}=ina+inb+cin;endmodule【例3.2】4位计数器module count4(out,reset,clk);output[3:0] out;input reset,clk;reg[3:0] out;always @(posedge clk)beginif (reset) out<=0; //同步复位else out<=out+1; //计数endendmodule【例3.3】4位全加器的仿真程序`timescale 1ns/1ns`include "adder4.v"module adder_tp; //测试模块的名字reg[3:0] a,b; //测试输入信号定义为reg型reg cin;wire[3:0] sum; //测试输出信号定义为wire型wire cout;integer i,j;adder4 adder(sum,cout,a,b,cin); //调用测试对象always #5 cin=~cin; //设定cin的取值initialbegina=0;b=0;cin=0;for(i=1;i<16;i=i+1)#10 a=i; //设定a的取值endinitialbeginfor(j=1;j<16;j=j+1)#10 b=j; //设定b的取值endinitial//定义结果显示格式begin$monitor($time,,,"%d + %d + %b={%b,%d}",a,b,cin,cout,sum);#160 $finish;endendmodule【例3.4】4位计数器的仿真程序`timescale 1ns/1ns`include "count4.v"module coun4_tp;reg clk,reset; //测试输入信号定义为reg型wire[3:0] out; //测试输出信号定义为wire型parameter DELY=100;count4 mycount(out,reset,clk); //调用测试对象always #(DELY/2) clk = ~clk; //产生时钟波形initialbegin//激励信号定义clk =0; reset=0;#DELY reset=1;#DELY reset=0;#(DELY*20) $finish;end//定义结果显示格式initial $monitor($time,,,"clk=%d reset=%d out=%d", clk, reset,out); endmodule【例3.5】“与-或-非”门电路module AOI(A,B,C,D,F); //模块名为AOI(端口列表A，B，C，D，F) input A,B,C,D; //模块的输入端口为A，B，C，Doutput F; //模块的输出端口为Fwire A,B,C,D,F; //定义信号的数据类型assign F= ~((A&B)|(C&D)); //逻辑功能描述endmodule【例5.1】用case语句描述的4选1数据选择器module mux4_1(out,in0,in1,in2,in3,sel);output out;input in0,in1,in2,in3;input[1:0] sel;reg out;always @(in0 or in1 or in2 or in3 or sel) //敏感信号列表case(sel)2'b00: out=in0;2'b01: out=in1;2'b10: out=in2;2'b11: out=in3;default: out=2'bx;endcaseendmodule【例5.2】同步置数、同步清零的计数器module count(out,data,load,reset,clk);output[7:0] out;input[7:0] data;input load,clk,reset;reg[7:0] out;always @(posedge clk) //clk上升沿触发beginif (!reset) out = 8'h00; //同步清0，低电平有效else if (load) out = data; //同步预置else out = out + 1; //计数endendmodule【例5.3】用always过程语句描述的简单算术逻辑单元`define add 3'd0`define minus 3'd1`define band 3'd2`define bor 3'd3`define bnot 3'd4module alu(out,opcode,a,b);output[7:0] out;reg[7:0] out;input[2:0] opcode; //操作码input[7:0] a,b; //操作数always@(opcode or a or b) //电平敏感的always块begincase(opcode)`add: out = a+b; //加操作`minus: out = a-b; //减操作`band: out = a&b; //求与`bor: out = a|b; //求或`bnot: out=~a; //求反default: out=8'hx; //未收到指令时，输出任意态endcaseendendmodule【例5.4】用initial过程语句对测试变量A、B、C赋值`timescale 1ns/1nsmodule test;reg A,B,C;initialbeginA = 0;B = 1;C = 0;#50 A = 1; B = 0;#50 A = 0; C = 1;#50 B = 1;#50 B = 0; C = 0;#50 $finish ;endendmodule【例5.5】用begin-end串行块产生信号波形`timescale 10ns/1nsmodule wave1;reg wave;parameter cycle=10;initialbeginwave=0;#(cycle/2) wave=1;#(cycle/2) wave=0;#(cycle/2) wave=1;#(cycle/2) wave=0;#(cycle/2) wave=1;#(cycle/2) $finish ;endinitial $monitor($time,,,"wave=%b",wave); endmodule【例5.6】用fork-join并行块产生信号波形`timescale 10ns/1nsmodule wave2;reg wave;parameter cycle=5;initialforkwave=0;#(cycle) wave=1;#(2*cycle) wave=0;#(3*cycle) wave=1;#(4*cycle) wave=0;#(5*cycle) wave=1;#(6*cycle) $finish;joininitial $monitor($time,,,"wave=%b",wave); endmodule【例5.7】持续赋值方式定义的2选1多路选择器module MUX21_1(out,a,b,sel);input a,b,sel;output out;assign out=(sel==0)?a:b;//持续赋值，如果sel为0，则out=a ；否则out=b endmodule【例5.8】阻塞赋值方式定义的2选1多路选择器module MUX21_2(out,a,b,sel);input a,b,sel;output out;reg out;always@(a or b or sel)beginif(sel==0) out=a; //阻塞赋值else out=b;endendmodule【例5.9】非阻塞赋值module non_block(c,b,a,clk);output c,b;input clk,a;reg c,b;always @(posedge clk)beginb<=a;c<=b;endendmodule【例5.10】阻塞赋值module block(c,b,a,clk);output c,b;input clk,a;reg c,b;always @(posedge clk)beginb=a;c=b;endendmodule【例5.11】模为60的BCD码加法计数器module count60(qout,cout,data,load,cin,reset,clk);output[7:0] qout;output cout;input[7:0] data;input load,cin,clk,reset;reg[7:0] qout;always @(posedge clk) //clk上升沿时刻计数if (reset) qout<=0; //同步复位else if(load) qout<=data; //同步置数else if(cin)beginif(qout[3:0]==9) //低位是否为9，是则beginqout[3:0]<=0; //回0，并判断高位是否为5if (qout[7:4]==5) qout[7:4]<=0;elseqout[7:4]<=qout[7:4]+1; //高位不为5，则加1endelse//低位不为9，则加1qout[3:0]<=qout[3:0]+1;endendassign cout=((qout==8'h59)&cin)?1:0; //产生进位输出信号endmodule【例5.12】BCD码—七段数码管显示译码器module decode4_7(decodeout,indec);output[6:0] decodeout;input[3:0] indec;reg[6:0] decodeout;always @(indec)begincase(indec) //用case语句进行译码4'd0:decodeout=7'b1111110;4'd1:decodeout=7'b0110000;4'd2:decodeout=7'b1101101;4'd3:decodeout=7'b1111001;4'd4:decodeout=7'b0110011;4'd5:decodeout=7'b1011011;4'd6:decodeout=7'b1011111;4'd7:decodeout=7'b1110000;4'd8:decodeout=7'b1111111;4'd9:decodeout=7'b1111011;default: decodeout=7'bx;endcaseend【例5.13】用casez描述的数据选择器module mux_casez(out,a,b,c,d,select); output out;input a,b,c,d;input[3:0] select;reg out;always @(select or a or b or c or d) begincasez(select)4'b???1: out = a;4'b??1?: out = b;4'b?1??: out = c;4'b1???: out = d;endcaseendendmodule【例5.14】隐含锁存器举例module buried_ff(c,b,a);output c;input b,a;reg c;always @(a or b)beginif((b==1)&&(a==1)) c=a&b;endendmodule【例5.15】用for语句描述的七人投票表决器module voter7(pass,vote);output pass;input[6:0] vote;reg[2:0] sum;integer i;reg pass;always @(vote)beginsum=0;for(i=0;i<=6;i=i+1) //for语句if(vote[i]) sum=sum+1;if(sum[2]) pass=1; //若超过4人赞成，则pass=1else pass=0;endendmodule【例5.16】用for语句实现2个8位数相乘module mult_for(outcome,a,b);parameter size=8;input[size:1] a,b; //两个操作数output[2*size:1] outcome; //结果reg[2*size:1] outcome;integer i;always @(a or b)beginoutcome=0;for(i=1; i<=size; i=i+1) //for语句if(b[i]) outcome=outcome +(a << (i-1));endendmodule【例5.17】用repeat实现8位二进制数的乘法module mult_repeat(outcome,a,b);parameter size=8;input[size:1] a,b;output[2*size:1] outcome;reg[2*size:1] temp_a,outcome;reg[size:1] temp_b;always @(a or b)beginoutcome=0;temp_a=a;temp_b=b;repeat(size) //repeat语句，size为循环次数beginif(temp_b[1]) //如果temp_b的最低位为1，就执行下面的加法outcome=outcome+temp_a;temp_a=temp_a<<1; //操作数a左移一位temp_b=temp_b>>1; //操作数b右移一位endendendmodule【例5.18】同一循环的不同实现方式module loop1; //方式1integer i;initialfor(i=0;i<4;i=i+1) //for语句begin$display(“i=%h”,i);endendmodulemodule loop2; //方式2integer i;initial begini=0;while(i<4) //while语句begin$display ("i=%h",i);i=i+1;endendendmodulemodule loop3; //方式3integer i;initial begini=0;repeat(4) //repeat语句begin$display ("i=%h",i);i=i+1;endendendmodule【例5.19】使用了`include语句的16位加法器`include "adder.v"module adder16(cout,sum,a,b,cin);output cout;parameter my_size=16;output[my_size-1:0] sum;input[my_size-1:0] a,b;input cin;adder my_adder(cout,sum,a,b,cin); //调用adder模块endmodule//下面是adder模块代码module adder(cout,sum,a,b,cin);parameter size=16;output cout;output[size-1:0] sum;input cin;input[size-1:0] a,b;assign {cout,sum}=a+b+cin;endmodule【例5.20】条件编译举例module compile(out,A,B);output out;input A,B;`ifdef add //宏名为addassign out=A+B;`elseassign out=A-B;`endifendmodule【例6.1】加法计数器中的进程module count(data,clk,reset,load,cout,qout);output cout;output[3:0] qout;reg[3:0] qout;input[3:0] data;input clk,reset,load;- 11 -always @(posedge clk) //进程1，always过程块beginif (!reset) qout= 4'h00; //同步清0，低电平有效else if (load) qout= data; //同步预置else qout=qout + 1; //加法计数endassign cout=(qout==4'hf)?1:0; //进程2，用持续赋值产生进位信号endmodule【例6.2】任务举例module alutask(code,a,b,c);input[1:0] code;input[3:0] a,b;output[4:0] c;reg[4:0] c;task my_and; //任务定义，注意无端口列表input[3:0] a,b; //a,b,out名称的作用域范围为task任务内部output[4:0] out;integer i;beginfor(i=3;i>=0;i=i-1)out[i]=a[i]&b[i]; //按位与endendtaskalways@(code or a or b)begincase(code)2'b00: my_and(a,b,c);/* 调用任务my_and，需注意端口列表的顺序应与任务定义中的一致，这里的a,b,c 分别对应任务定义中的a,b,out */2'b01: c=a|b; //或2'b10: c=a-b; //相减2'b11: c=a+b; //相加endcaseendendmodule- 12 -【例6.3】测试程序`include "alutask.v"module alu_tp;reg[3:0] a,b;reg[1:0] code;wire[4:0] c;parameter DELY = 100;alutask ADD(code,a,b,c); //调用被测试模块initial begincode=4'd0; a= 4'b0000; b= 4'b1111;#DELY code=4'd0; a= 4'b0111; b= 4'b1101;#DELY code=4'd1; a= 4'b0001; b= 4'b0011;#DELY code=4'd2; a= 4'b1001; b= 4'b0011;#DELY code=4'd3; a= 4'b0011; b= 4'b0001;#DELY code=4'd3; a= 4'b0111; b= 4'b1001;#DELY $finish;endinitial $monitor($time,,,"code=%b a=%b b=%b c=%b", code,a,b,c);endmodule【例6.4】函数function[7:0] get0;input[7:0] x;reg[7:0] count;integer i;begincount=0;for (i=0;i<=7;i=i+1)if (x[i]=1'b0) count=count+1;get0=count;endendfunction【例6.5】用函数和case语句描述的编码器（不含优先顺序）module code_83(din,dout);input[7:0] din;output[2:0] dout;- 13 -function[2:0] code; //函数定义input[7:0] din; //函数只有输入，输出为函数名本身casex (din)8'b1xxx_xxxx : code = 3'h7;8'b01xx_xxxx : code = 3'h6;8'b001x_xxxx : code = 3'h5;8'b0001_xxxx : code = 3'h4;8'b0000_1xxx : code = 3'h3;8'b0000_01xx : code = 3'h2;8'b0000_001x : code = 3'h1;8'b0000_000x : code = 3'h0;default: code = 3'hx;endcaseendfunctionassign dout = code(din) ; //函数调用endmodule【例6.6】阶乘运算函数module funct(clk,n,result,reset);output[31:0] result;input[3:0] n;input reset,clk;reg[31:0] result;always @(posedge clk) //在clk的上升沿时执行运算beginif(!reset) result<=0; //复位else beginresult <= 2 * factorial(n); //调用factorial函数endendfunction[31:0] factorial; //阶乘运算函数定义（注意无端口列表）input[3:0] opa; //函数只能定义输入端，输出端口为函数名本身reg[3:0] i;beginfactorial = opa ? 1 : 0;for(i= 2; i <= opa; i = i+1) //该句若要综合通过，opa应赋具体的数值factorial = i* factorial; //阶乘运算end- 14 -endfunctionendmodule【例6.7】测试程序`define clk_cycle 50`include "funct.v"module funct_tp;reg[3:0] n;reg reset,clk;wire[31:0] result;initial//定义激励向量beginn=0; reset=1; clk=0;for(n=0;n<=15;n=n+1)#100 n=n;endinitial $monitor($time,,,"n=%d result=%d",n,result);//定义输出显示格式always # `clk_cycle clk=~clk; //产生时钟信号funct funct_try(.clk(clk),.n(n),.result(result),.reset(reset));//调用被测试模块endmodule【例6.8】顺序执行模块1module serial1(q,a,clk);output q,a;input clk;reg q,a;always @(posedge clk)beginq=~q;a=~q;endendmodule【例6.9】顺序执行模块2module serial2(q,a,clk);output q,a;- 15 -input clk;reg q,a;always @(posedge clk)begina=~q;q=~q;endendmodule【例6.10】并行执行模块1module paral1(q,a,clk);output q,a;input clk;reg q,a;always @(posedge clk)beginq=~q;endalways @(posedge clk)begina=~q;endendmodule【例6.11】并行执行模块2module paral2(q,a,clk);output q,a;input clk;reg q,a;always @(posedge clk)begina=~q;endalways @(posedge clk)beginq=~q;endendmodule【例7.1】调用门元件实现的4选1 MUX - 16 -module mux4_1a(out,in1,in2,in3,in4,cntrl1,cntrl2);output out;input in1,in2,in3,in4,cntrl1,cntrl2;wire notcntrl1,notcntrl2,w,x,y,z;not(notcntrl1,cntrl2),(notcntrl2,cntrl2);and (w,in1,notcntrl1,notcntrl2),(x,in2,notcntrl1,cntrl2),(y,in3,cntrl1,notcntrl2),(z,in4,cntrl1,cntrl2);or (out,w,x,y,z);endmodule【例7.2】用case语句描述的4选1 MUXmodule mux4_1b(out,in1,in2,in3,in4,cntrl1,cntrl2);output out;input in1,in2,in3,in4,cntrl1,cntrl2;reg out;always@(in1 or in2 or in3 or in4 or cntrl1 or cntrl2)case({cntrl1,cntrl2})2'b00:out=in1;2'b01:out=in2;2'b10:out=in3;2'b11:out=in4;default:out=2'bx;endcaseendmodule【例7.3】行为描述方式实现的4位计数器module count4(clk,clr,out);input clk,clr;output[3:0] out;reg[3:0] out;always @(posedge clk or posedge clr)beginif (clr) out<=0;else out<=out+1;endendmodule- 17 -【例7.4】数据流方式描述的4选1 MUXmodule mux4_1c(out,in1,in2,in3,in4,cntrl1,cntrl2);output out;input in1,in2,in3,in4,cntrl1,cntrl2;assign out=(in1 & ~cntrl1 & ~cntrl2)|(in2 & ~cntrl1 & cntrl2)| (in3 & cntrl1 & ~cntrl2)|(in4 & cntrl1 & cntrl2);endmodule【例7.5】用条件运算符描述的4选1 MUXmodule mux4_1d(out,in1,in2,in3,in4,cntrl1,cntrl2);output out;input in1,in2,in3,in4,cntrl1,cntrl2;assign out=cntrl1 ? (cntrl2 ? in4:in3):(cntrl2 ? in2:in1);endmodule【例7.6】门级结构描述的2选1MUXmodule mux2_1a(out,a,b,sel);output out;input a,b,sel;not (sel_,sel);and(a1,a,sel_),(a2,b,sel);or (out,a1,a2);endmodule【例7.7】行为描述的2选1MUXmodule mux2_1b(out,a,b,sel);output out;input a,b,sel;reg out;always @(a or b or sel)beginif(sel) out = b;else out = a;endendmodule【例7.8】数据流描述的2选1MUXmodule MUX2_1c(out,a,b,sel);output out;- 18 -input a,b,sel;assign out = sel ? b : a;endmodule【例7.9】调用门元件实现的1位半加器module half_add1(a,b,sum,cout);input a,b;output sum,cout;and(cout,a,b);xor(sum,a,b);endmodule【例7.10】数据流方式描述的1位半加器module half_add2(a,b,sum,cout);input a,b;output sum,cout;assign sum=a^b;assign cout=a&b;endmodule【例7.11】采用行为描述的1位半加器module half_add3(a,b,sum,cout);input a,b;output sum,cout;reg sum,cout;always @(a or b)begincase ({a,b}) //真值表描述2'b00: begin sum=0; cout=0; end2'b01: begin sum=1; cout=0; end2'b10: begin sum=1; cout=0; end2'b11: begin sum=0; cout=1; endendcaseendendmodule【例7.12】采用行为描述的1位半加器module half_add4(a,b,sum,cout);input a,b;output sum,cout;- 19 -reg sum,cout;always @(a or b)beginsum= a^b;cout=a&b;endendmodule【例7.13】调用门元件实现的1位全加器module full_add1(a,b,cin,sum,cout);input a,b,cin;output sum,cout;wire s1,m1,m2,m3;and (m1,a,b),(m2,b,cin),(m3,a,cin);xor(s1,a,b),(sum,s1,cin);or(cout,m1,m2,m3);endmodule【例7.14】数据流描述的1位全加器module full_add2(a,b,cin,sum,cout);input a,b,cin;output sum,cout;assign sum = a ^ b ^ cin;assign cout = (a & b)|(b & cin)|(cin & a);endmodule【例7.15】1位全加器module full_add3(a,b,cin,sum,cout);input a,b,cin;output sum,cout;assign {cout,sum}=a+b+cin;endmodule【例7.16】行为描述的1位全加器module full_add4(a,b,cin,sum,cout);input a,b,cin;output sum,cout;- 20 -reg sum,cout; //在always块中被赋值的变量应定义为reg型reg m1,m2,m3;always @(a or b or cin)beginsum = (a ^ b) ^ cin;m1 = a & b;m2 = b & cin;m3 = a & cin;cout = (m1|m2)|m3;endendmodule【例7.17】混合描述的1位全加器 module full_add5(a,b,cin,sum,cout);input a,b,cin;output sum,cout;reg cout,m1,m2,m3; //在always块中被赋值的变量应定义为reg型wire s1;xor x1(s1,a,b); //调用门元件always @(a or b or cin) //always块语句beginm1 = a & b;m2 = b & cin;m3 = a & cin;cout = (m1| m2) | m3;endassign sum = s1 ^ cin; //assign持续赋值语句endmodule【例7.18】结构描述的4位级连全加器 `include "full_add1.v"module add4_1(sum,cout,a,b,cin);output[3:0] sum;output cout;input[3:0] a,b;input cin;full_add1 f0(a[0],b[0],cin,sum[0],cin1); //级连描述full_add1 f1(a[1],b[1],cin1,sum[1],cin2);full_add1 f2(a[2],b[2],cin2,sum[2],cin3);- 21 -full_add1 f3(a[3],b[3],cin3,sum[3],cout);endmodule【例7.19】数据流描述的4位全加器module add4_2(cout,sum,a,b,cin);output[3:0] sum;output cout;input[3:0] a,b;input cin;assign {cout,sum}=a+b+cin;endmodule【例7.20】行为描述的4位全加器module add4_3(cout,sum,a,b,cin);output[3:0] sum;output cout;input[3:0] a,b;input cin;reg[3:0] sum;reg cout;always @(a or b or cin)begin{cout,sum}=a+b+cin;endendmodule【例8.1】$time与$realtime的区别`timescale 10ns/1nsmodule time_dif;reg ts;parameter delay=2.6;initialbegin#delay ts=1;#delay ts=0;#delay ts=1;#delay ts=0;endinitial $monitor($time,,,"ts=%b",ts); //使用函数$time - 22 -endmodule【例8.2】$random函数的使用`timescale 10ns/1nsmodule random_tp;integer data;integer i;parameter delay=10;initial $monitor($time,,,"data=%b",data);initial beginfor(i=0; i<=100; i=i+1)#delay data=$random; //每次产生一个随机数endendmodule【例8.3】1位全加器进位输出UDP元件primitive carry_udp(cout,cin,a,b);input cin,a,b;output cout;table//cin a b : cout //真值表0 0 0 : 0;0 1 0 : 0;0 0 1 : 0;0 1 1 : 1;1 0 0 : 0;1 0 1 : 1;1 1 0 : 1;1 1 1 : 1;endtableendprimitive【例8.4】包含x态输入的1位全加器进位输出UDP元件primitive carry_udpx1(cout,cin,a,b);input cin,a,b;output cout;table// cin a b : cout //真值表0 0 0 : 0;- 23 -0 1 0 : 0;0 0 1 : 0;0 1 1 : 1;1 0 0 : 0;1 0 1 : 1;1 1 0 : 1;1 1 1 : 1;0 0 x : 0; //只要有两个输入为0，则进位输出肯定为00 x 0 : 0;x 0 0 : 0;1 1 x : 1; //只要有两个输入为1，则进位输出肯定为11 x 1 : 1;x 1 1 : 1;endtableendprimitive【例8.5】用简缩符“？”表述的1位全加器进位输出UDP元件primitive carry_udpx2(cout,cin,a,b);input cin,a,b;output cout;table// cin a b : cout //真值表? 0 0 : 0; //只要有两个输入为0，则进位输出肯定为00 ? 0 : 0;0 0 ? : 0;? 1 1 : 1; //只要有两个输入为1，则进位输出肯定为11 ? 1 : 1;1 1 ? : 1;endtableendprimitive【例8.6】3选1多路选择器UDP元件primitive mux31(Y,in0,in1,in2,s2,s1);input in0,in1,in2,s2,s1;output Y;table//in0 in1 in2 s2 s1 : Y0 ? ? 0 0 : 0; //当s2s1=00时，Y=in01 ? ? 0 0 : 1;? 0 ? 0 1 : 0; //当s2s1=01时，Y=in1- 24 -? 1 ? 0 1 : 1;? ? 0 1 ? : 0; //当s2s1=1？时，Y=in2? ? 1 1 ? : 1;0 0 ? 0 ? : 0;1 1 ? 0 ? : 1;0 ? 0 ? 0 : 0;1 ? 1 ? 0 : 1;? 0 0 ? 1 : 0;? 1 1 ? 1 : 1;endtableendprimitive【例8.7】电平敏感的1位数据锁存器UDP元件primitive latch(Q,clk,reset,D);input clk,reset,D;output Q;reg Q;initial Q = 1'b1; //初始化table// clk reset D : state : Q? 1 ? : ? : 0 ; //reset=1，则不管其他端口为什么值，输出都为00 0 0 : ? : 0 ; //clk=0，锁存器把D端的输入值输出0 0 1 : ? : 1 ;1 0 ? : ? : - ; //clk=1，锁存器的输出保持原值，用符号“-”表示endtableendprimitive【例8.8】上升沿触发的D触发器UDP元件primitive DFF(Q,D,clk);output Q;input D,clk;reg Q;table//clk D : state : Q(01) 0 : ? : 0; //上升沿到来，输出Q=D(01) 1 : ? : 1;(0x) 1 : 1 : 1;(0x) 0 : 0 : 0;(?0) ? : ? : -; //没有上升沿到来，输出Q保持原值? (??) : ? : - ; //时钟不变，输出也不变- 25 -endprimitive【例8.9】带异步置1和异步清零的上升沿触发的D触发器UDP元件primitive DFF_UDP(Q,D,clk,clr,set);output Q;input D,clk,clr,set;reg Q;table// clk D clr s et : state : Q(01) 1 0 0 : ? : 0;(01) 1 0 x : ? : 0;? ? 0 x : 0 : 0;(01) 0 0 0 : ? : 1;(01) 0 x 0 : ? : 1;? ? x 0 : 1 : 1;(x1) 1 0 0 : 0 : 0;(x1) 0 0 0 : 1 : 1;(0x) 1 0 0 : 0 : 0;(0x) 0 0 0 : 1 : 1;? ? 1 ? : ? : 1; //异步复位? ? 0 1 : ? : 0; //异步置1n ? 0 0 : ? : -;? * ? ? : ? : -;? ? (?0) ? : ? : -;? ? ? (?0): ? : -;? ? ? ? : ? : x;endtableendprimitive【例8.12】延迟定义块举例module delay(out,a,b,c);output out;input a,b,c;and a1(n1,a,b);or o1(out,c,n1);specify(a=>out)=2;(b=>out)=3;(c=>out)=1;- 26 -endmodule【例8.13】激励波形的描述'timescale 1ns/1nsmodule test1;reg A,B,C;initialbegin//激励波形描述A = 0;B = 1;C = 0;#100 C = 1;#100 A = 1; B = 0;#100 A = 0;#100 C = 0;#100 $finish;endinitial $monitor($time,,,"A=%d B=%d C=%d",A,B,C); //显示endmodule【例8.15】用always过程块产生两个时钟信号module test2;reg clk1,clk2;parameter CYCLE = 100;alwaysbegin{clk1,clk2} = 2'b10;#(CYCLE/4) {clk1,clk2} = 2'b01;#(CYCLE/4) {clk1,clk2} = 2'b11;#(CYCLE/4) {clk1,clk2} = 2'b00;#(CYCLE/4) {clk1,clk2} = 2'b10;endinitial $monitor($time,,,"clk1=%b clk2=%b",clk1,clk2);endmodule【例8.17】存储器在仿真程序中的应用module ROM(addr,data,oe);output[7:0] data; //数据信号input[14:0] addr; //地址信号input oe; //读使能信号，低电平有效- 27 -reg[7:0] mem[0:255]; //存储器定义parameter DELAY = 100;assign #DELAY data=(oe==0) ? mem[addr] : 8'hzz;initial $readmemh("rom.hex",mem); //从文件中读入数据endmodule【例8.18】8位乘法器的仿真程序`timescale 10ns/1nsmodule mult_tp; //测试模块的名字reg[7:0] a,b; //测试输入信号定义为reg型wire [15:0] out; //测试输出信号定义为wire型integer i,j;mult8 m1(out,a,b); //调用测试对象//激励波形设定initialbegina=0;b=0;for(i=1;i<255;i=i+1)#10 a=i;endinitialbeginfor(j=1;j<255;j=j+1)#10 b=j;endinitial//定义结果显示格式begin$monitor($time,,,"%d * %d= %d",a,b,out);#2560 $finish;endendmodulemodule mult8(out, a, b); //8位乘法器源代码parameter size=8;input[size:1] a,b; //两个操作数output[2*size:1] out; //结果assign out=a*b; //乘法运算符- 28 -endmodule【例8.19】8位加法器的仿真程序`timescale 1ns/1nsmodule add8_tp; //仿真模块无端口列表reg[7:0] A,B; //输入激励信号定义为reg型reg cin;wire[7:0] SUM; //输出信号定义为wire型wire cout;parameter DELY = 100;add8 AD1(SUM,cout,A,B,cin); //调用测试对象initial begin//激励波形设定A= 8'd0; B= 8'd0; cin=1'b0;#DELY A= 8'd100; B= 8'd200; cin=1'b1;#DELY A= 8'd200; B= 8'd88;#DELY A= 8'd210; B= 8'd18; cin=1'b0;#DELY A= 8'd12; B= 8'd12;#DELY A= 8'd100; B= 8'd154;#DELY A= 8'd255; B= 8'd255; cin=1'b1;#DELY $finish;end//输出格式定义initial $monitor($time,,,"%d + %d + %b = {%b, %d}",A,B,cin,cout,SUM); endmodulemodule add8(SUM,cout,A,B,cin); //待测试的8位加法器模块output[7:0] SUM;output cout;input[7:0] A,B;input cin;assign {cout,SUM}=A+B+cin;endmodule【例8.20】2选1多路选择器的仿真`timescale 1ns/1nsmodule mux_tp;reg a,b,sel;wire out;- 29 -MUX2_1 m1(out,a,b,sel); //调用待测试模块initialbegina=1'b0; b=1'b0; sel=1'b0;#5 sel=1'b1;#5 a=1'b1; s el=1'b0;#5 sel=1'b1;#5 a=1'b0; b=1'b1; sel=1'b0;#5 sel=1'b1;#5 a=1'b1; b=1'b1; sel=1'b0;#5 sel=1'b1;endinitial $monitor($time,,,"a=%b b=%b sel=%b out=%b",a,b,sel,out);endmodulemodule MUX2_1(out,a,b,sel); //待测试的2选1MUX模块input a,b,sel;output out;not #(0.4,0.3) (sel_,sel); //#(0.4,0.3)为门延时and #(0.7,0.6) (a1,a,sel_);and #(0.7,0.6) (a2,b,sel);or #(0.7,0.6) (out,a1,a2);endmodule【例8.21】8位计数器的仿真`timescale 10ns/1nsmodule count8_tp;reg clk,reset; //输入激励信号定义为reg型wire[7:0] qout; //输出信号定义为wire型parameter DELY=100;counter C1(qout,reset,clk); //调用测试对象always #(DELY/2) clk = ~clk; //产生时钟波形initialbegin//激励波形定义clk =0; reset=0;- 30 -#DELY reset=1;#DELY reset=0;#(DELY*300) $finish;end//结果显示initial $monitor($time,,,"clk=%d reset=%d qout=%d",clk,reset,qout); endmodulemodule counter(qout,reset,clk); //待测试的8位计数器模块output[7:0] qout;input clk,reset;reg[7:0] qout;always @(posedge clk)begin if (reset) qout<=0;else qout<=qout+1;endendmodule【例9.1】基本门电路的几种描述方法（1）门级结构描述module gate1(F,A,B,C,D);input A,B,C,D;output F;nand(F1,A,B); //调用门元件and(F2,B,C,D);or(F,F1,F2);endmodule（2）数据流描述module gate2(F,A,B,C,D);input A,B,C,D;output F;assign F=(A&B)|(B&C&D); //assign持续赋值endmodule（3）行为描述module gate3(F,A,B,C,D);input A,B,C,D;output F;- 31 -reg F;always @(A or B or C or D) //过程赋值beginF=(A&B)|(B&C&D);endendmodule【例9.2】用bufif1关键字描述的三态门module tri_1(in,en,out);input in,en;output out;tri out;bufif1 b1(out,in,en); //注意三态门端口的排列顺序endmodule【例9.3】用assign语句描述的三态门module tri_2(out,in,en);output out;input in,en;assign out = en ? in : 'bz;//若en=1，则out=in；若en=0，则out为高阻态endmodule【例9.4】三态双向驱动器module bidir(tri_inout,out,in,en,b);inout tri_inout;output out;input in,en,b;assign tri_inout = en ? in : 'bz;assign out = tri_inout ^ b;endmodule【例9.5】三态双向驱动器module bidir2(bidir,en,clk);inout[7:0] bidir;input en,clk;reg[7:0] temp;assign bidir= en ? temp : 8'bz;always @(posedge clk)begin- 32 -if(en) temp=bidir;else temp=temp+1;endendmodule【例9.6】3-8译码器module decoder_38(out,in);output[7:0] out;input[2:0] in;reg[7:0] out;always @(in)begincase(in)3'd0: out=8'b11111110;3'd1: out=8'b11111101;3'd2: out=8'b11111011;3'd3: out=8'b11110111;3'd4: out=8'b11101111;3'd5: out=8'b11011111;3'd6: out=8'b10111111;3'd7: out=8'b01111111;endcaseendendmodule【例9.7】8-3优先编码器module encoder8_3(none_on,outcode,a,b,c,d,e,f,g,h);output none_on;output[2:0] outcode;input a,b,c,d,e,f,g,h;reg[3:0] outtemp;assign {none_on,outcode}=outtemp;always @(a or b or c or d or e or f or g or h)beginif(h) outtemp=4'b0111;else if(g) outtemp=4'b0110;else if(f) outtemp=4'b0101;else if(e) outtemp=4'b0100;else if(d) outtemp=4'b0011;else if(c) outtemp=4'b0010;- 33 -else if(b) outtemp=4'b0001;else if(a) outtemp=4'b0000;else outtemp=4'b1000;endendmodule【例9.8】用函数定义的8-3优先编码器module code_83(din, dout);input[7:0] din;output[2:0] dout;function[2:0] code; //函数定义input[7:0] din; //函数只有输入端口，输出为函数名本身if (din[7]) code = 3'd7;else if (din[6]) code = 3'd6;else if (din[5]) code = 3'd5;else if (din[4]) code = 3'd4;else if (din[3]) code = 3'd3;else if (din[2]) code = 3'd2;else if (din[1]) code = 3'd1;else code = 3'd0;endfunctionassign dout = code(din); //函数调用endmodule【例9.9】七段数码管译码器module decode47(a,b,c,d,e,f,g,D3,D2,D1,D0);output a,b,c,d,e,f,g;input D3,D2,D1,D0; //输入的4位BCD码reg a,b,c,d,e,f,g;always @(D3 or D2 or D1 or D0)begincase({D3,D2,D1,D0}) //用case语句进行译码4'd0: {a,b,c,d,e,f,g}=7'b1111110;4'd1: {a,b,c,d,e,f,g}=7'b0110000;4'd2: {a,b,c,d,e,f,g}=7'b1101101;4'd3: {a,b,c,d,e,f,g}=7'b1111001;4'd4: {a,b,c,d,e,f,g}=7'b0110011;4'd5: {a,b,c,d,e,f,g}=7'b1011011;- 34 -。
Verilog程序电子琴梁祝
8'd 1:{high,med,low}=12'b0000_0000_0011;
8'd 2:{high,med,low}=12'b0000_0000_0011;
8'd 3:{high,med,low}=12'b0000_0000_0011;
8'd32:{high,med,low}=12'b0000_0010_0000;
8'd33:{high,med,low}=12'b0000_0010_0000;
8'd34:{high,med,low}=12'b0000_0010_0000;
8'd35:{high,med,low}=12'b0000_0011_0000;
endcase
end
always@(posedge clk_4hz)
begin
if(counter==8'd50)
counter=8'd0;
else
counter=counter+1'b1;
case(counter)
8'd40:{high,med,low}=12'b0000_0000_0101;
8'd41:{high,med,low}=12'b0000_0000_0101;
8'd42:{high,med,low}=12'b0000_0000_0101;
8'd43:{high,med,low}=12'b0000_0000_0110;
verilog优化逻辑的例子
verilog优化逻辑的例子Verilog是一种硬件描述语言，用于描述数字电路的行为和结构。
在设计数字电路时，优化逻辑是非常重要的，可以使电路具有更高的性能和更低的功耗。
下面列举了10个使用Verilog优化逻辑的例子。
1. 优化逻辑运算：在设计数字电路时，经常需要使用逻辑运算符，如与、或、非等。
通过合理地使用逻辑运算符，可以减少电路中门的数量，从而提高电路的性能和速度。
2. 优化布尔表达式：布尔表达式是用于描述逻辑电路的重要工具。
通过简化布尔表达式，可以减少电路中的逻辑门数量，从而提高电路的效率。
3. 优化时序逻辑：时序逻辑是一种特殊的逻辑电路，它的输出取决于输入信号的顺序和时序。
通过合理地设计时序逻辑，可以减少电路中的延迟，提高电路的速度和性能。
4. 优化组合逻辑：组合逻辑是一种不带时钟的逻辑电路，它的输出仅取决于当前的输入信号。
通过合理地设计组合逻辑，可以减少电路中的延迟和功耗，提高电路的性能。
5. 优化多输入逻辑：多输入逻辑是一种具有多个输入信号的逻辑电路。
通过优化多输入逻辑，可以减少电路中的逻辑门数量，提高电路的速度和功耗。
6. 优化状态机：状态机是一种用于描述电路行为的模型。
通过优化状态机的设计，可以减少电路中的逻辑门数量，提高电路的性能和速度。
7. 优化数据通路：数据通路是用于处理数据的路径，包括寄存器、加法器、乘法器等。
通过优化数据通路的设计，可以减少电路中的延迟和功耗，提高电路的性能。
8. 优化存储器设计：存储器是用于存储数据的电路，包括寄存器、RAM、ROM等。
通过优化存储器的设计，可以减少电路中的延迟和功耗，提高电路的性能。
9. 优化时钟频率：时钟频率是电路运行的速度，通过优化电路的设计，可以提高电路的时钟频率，从而提高电路的性能和速度。
10. 优化功耗：功耗是电路消耗的能量，通过优化电路的设计，可以减少电路中的功耗，提高电路的能效。
通过Verilog优化逻辑的设计，可以提高电路的性能和速度，减少电路的延迟和功耗，从而实现更高效的数字电路设计。
Verilog的135个经典设计实例
王金明《Verilog HDL程序设计教程》【例3.1】4位全加器module adder4(cout,sum,ina,inb,cin);output[3:0] sum;output cout;input[3:0] ina,inb;input cin;assign {cout,sum}=ina+inb+cin;endmodule【例3.2】4位计数器module count4(out,reset,clk);output[3:0] out;input reset,clk;reg[3:0] out;always @(posedge clk)beginif (reset) out<=0; //同步复位else out<=out+1; //计数endendmodule【例3.3】4位全加器的仿真程序`timescale 1ns/1ns`include "adder4.v"module adder_tp; //测试模块的名字reg[3:0] a,b; //测试输入信号定义为reg型reg cin;wire[3:0] sum; //测试输出信号定义为wire型wire cout;integer i,j;adder4 adder(sum,cout,a,b,cin); //调用测试对象always #5 cin=~cin; //设定cin的取值initialbegina=0;b=0;cin=0;for(i=1;i<16;i=i+1)#10 a=i; //设定a的取值end- 1 - 程序文本initialbeginfor(j=1;j<16;j=j+1)#10 b=j; //设定b的取值endinitial //定义结果显示格式begin$monitor($time,,,"%d + %d + %b={%b,%d}",a,b,cin,cout,sum); #160 $finish;endendmodule【例3.4】4位计数器的仿真程序`timescale 1ns/1ns`include "count4.v"module coun4_tp;reg clk,reset; //测试输入信号定义为reg型wire[3:0] out; //测试输出信号定义为wire型parameter DELY=100;count4 mycount(out,reset,clk); //调用测试对象always #(DELY/2) clk = ~clk; //产生时钟波形initialbegin //激励信号定义clk =0; reset=0;#DELY reset=1;#DELY reset=0;#(DELY*20) $finish;end//定义结果显示格式initial $monitor($time,,,"clk=%d reset=%d out=%d", clk, reset,out);endmodule【例3.5】“与-或-非”门电路module AOI(A,B,C,D,F); //模块名为AOI(端口列表A B C D F)input A,B,C,D; //模块的输入端口为A B C Doutput F; //模块的输出端口为F- 2 -王金明《Verilog HDL程序设计教程》wire A,B,C,D,F; //定义信号的数据类型 assign F= ~((A&B)|(C&D)); //逻辑功能描述endmodule【例5.1】用case语句描述的4选1数据选择器module mux4_1(out,in0,in1,in2,in3,sel);output out;input in0,in1,in2,in3;input[1:0] sel;reg out;always @(in0 or in1 or in2 or in3 or sel) //敏感信号列表 case(sel)2'b00: out=in0;2'b01: out=in1;2'b10: out=in2;2'b11: out=in3;default: out=2'bx;endcaseendmodule【例5.2】同步置数、同步清零的计数器module count(out,data,load,reset,clk);output[7:0] out;input[7:0] data;input load,clk,reset;reg[7:0] out;always @(posedge clk) //clk上升沿触发beginif (!reset) out = 8'h00; //同步清0低电平有效else if (load) out = data; //同步预置else out = out + 1; //计数endendmodule【例5.3】用always过程语句描述的简单算术逻辑单元`define add 3'd0`define minus 3'd1`define band 3'd2`define bor 3'd3`define bnot 3'd4- 3 - 程序文本module alu(out,opcode,a,b);output[7:0] out;reg[7:0] out;input[2:0] opcode; //操作码input[7:0] a,b; //操作数always@(opcode or a or b) //电平敏感的always块 begincase(opcode)`add: out = a+b; //加操作`minus: out = a-b; //减操作`band: out = a&b; //求与`bor: out = a|b; //求或`bnot: out=~a; //求反default: out=8'hx; //未收到指令时输出任意态 endcaseendendmodule【例5.4】用initial过程语句对测试变量A、B、C赋值 `timescale 1ns/1nsmodule test;reg A,B,C;initialbeginA = 0;B = 1;C = 0;#50 A = 1; B = 0;#50 A = 0; C = 1;#50 B = 1;#50 B = 0; C = 0;#50 $finish ;endendmodule【例5.5】用begin-end串行块产生信号波形 `timescale 10ns/1nsmodule wave1;reg wave;parameter cycle=10;initialbegin- 4 -王金明《Verilog HDL程序设计教程》wave=0;#(cycle/2) wave=1;#(cycle/2) wave=0;#(cycle/2) wave=1;#(cycle/2) wave=0;#(cycle/2) wave=1;#(cycle/2) $finish ;endinitial $monitor($time,,,"wave=%b",wave); endmodule【例5.6】用fork-join并行块产生信号波形`timescale 10ns/1nsmodule wave2;reg wave;parameter cycle=5;initialforkwave=0;#(cycle) wave=1;#(2*cycle) wave=0;#(3*cycle) wave=1;#(4*cycle) wave=0;#(5*cycle) wave=1;#(6*cycle) $finish;joininitial $monitor($time,,,"wave=%b",wave); endmodule【例5.7】持续赋值方式定义的2选1多路选择器module MUX21_1(out,a,b,sel);input a,b,sel;output out;assign out=(sel==0)?a:b;//持续赋值如果sel为0则out=a 否则out=b endmodule【例5.8】阻塞赋值方式定义的2选1多路选择器module MUX21_2(out,a,b,sel); input a,b,sel;- 5 - 程序文本output out;reg out;always@(a or b or sel)beginif(sel==0) out=a; //阻塞赋值 else out=b;endendmodule【例5.9】非阻塞赋值module non_block(c,b,a,clk);output c,b;input clk,a;reg c,b;always @(posedge clk)beginb<=a;c<=b;endendmodule【例5.10】阻塞赋值module block(c,b,a,clk);output c,b;input clk,a;reg c,b;always @(posedge clk)beginb=a;c=b;endendmodule【例5.11】模为60的BCD码加法计数器module count60(qout,cout,data,load,cin,reset,clk); output[7:0] qout;output cout;input[7:0] data;input load,cin,clk,reset;reg[7:0] qout;always @(posedge clk) //clk上升沿时刻计数- 6 -王金明《Verilog HDL程序设计教程》beginif (reset) qout<=0; //同步复位else if(load) qout<=data; //同步置数else if(cin)beginif(qout[3:0]==9) //低位是否为9是则beginqout[3:0]<=0; //回0并判断高位是否为5if (qout[7:4]==5) qout[7:4]<=0;elseqout[7:4]<=qout[7:4]+1; //高位不为5则加1endelse //低位不为9则加1qout[3:0]<=qout[3:0]+1;endendassign cout=((qout==8'h59)&cin)?1:0; //产生进位输出信号endmodule【例5.12】BCD码—七段数码管显示译码器module decode4_7(decodeout,indec);output[6:0] decodeout;input[3:0] indec;reg[6:0] decodeout;always @(indec)begincase(indec) //用case语句进行译码4'd0:decodeout=7'b1111110;4'd1:decodeout=7'b0110000;4'd2:decodeout=7'b1101101;4'd3:decodeout=7'b1111001;4'd4:decodeout=7'b0110011;4'd5:decodeout=7'b1011011;4'd6:decodeout=7'b1011111;4'd7:decodeout=7'b1110000;4'd8:decodeout=7'b1111111;4'd9:decodeout=7'b1111011;default: decodeout=7'bx;endcaseend- 7 - 程序文本endmodule【例5.13】用casez描述的数据选择器 module mux_casez(out,a,b,c,d,select); output out;input a,b,c,d;input[3:0] select;reg out;always @(select or a or b or c or d)begincasez(select)4'b???1: out = a;4'b??1?: out = b;4'b?1??: out = c;4'b1???: out = d;endcaseendendmodule【例5.14】隐含锁存器举例module buried_ff(c,b,a);output c;input b,a;reg c;always @(a or b)beginif((b==1)&&(a==1)) c=a&b;endendmodule【例5.15】用for语句描述的七人投票表决器module voter7(pass,vote);output pass;input[6:0] vote;reg[2:0] sum;integer i;reg pass;always @(vote)beginsum=0;- 8 -王金明《Verilog HDL程序设计教程》for(i=0;i<=6;i=i+1) //for语句if(vote[i]) sum=sum+1;if(sum[2]) pass=1; //若超过4人赞成则pass=1 else pass=0;endendmodule【例5.16】用for语句实现2个8位数相乘module mult_for(outcome,a,b);parameter size=8;input[size:1] a,b; //两个操作数output[2*size:1] outcome; //结果reg[2*size:1] outcome;integer i;always @(a or b)beginoutcome=0;for(i=1; i<=size; i=i+1) //for语句if(b[i]) outcome=outcome +(a << (i-1));endendmodule【例5.17】用repeat实现8位二进制数的乘法module mult_repeat(outcome,a,b);parameter size=8;input[size:1] a,b;output[2*size:1] outcome;reg[2*size:1] temp_a,outcome;reg[size:1] temp_b;always @(a or b)beginoutcome=0;temp_a=a;temp_b=b;repeat(size) //repeat语句size为循环次数beginif(temp_b[1]) //如果temp_b的最低位为1就执行下面的加法 outcome=outcome+temp_a;temp_a=temp_a<<1; //操作数a左移一位- 9 - 程序文本temp_b=temp_b>>1; //操作数b右移一位endendendmodule【例5.18】同一循环的不同实现方式 module loop1; //方式1integer i;initialfor(i=0;i<4;i=i+1) //for语句begin$display(“i=%h”,i);endendmodulemodule loop2; //方式2integer i;initial begini=0;while(i<4) //while语句begin$display ("i=%h",i);i=i+1;endendendmodulemodule loop3; //方式3integer i;initial begini=0;repeat(4) //repeat语句begin$display ("i=%h",i);i=i+1;endendendmodule【例5.19】使用了`include语句的16位加法器- 10 -王金明《Verilog HDL程序设计教程》`include "adder.v" module adder16(cout,sum,a,b,cin);output cout;parameter my_size=16;output[my_size-1:0] sum;input[my_size-1:0] a,b;input cin;adder my_adder(cout,sum,a,b,cin); //调用adder模块endmodule//下面是adder模块代码module adder(cout,sum,a,b,cin);parameter size=16;output cout;output[size-1:0] sum;input cin;input[size-1:0] a,b;assign {cout,sum}=a+b+cin;endmodule【例5.20】条件编译举例module compile(out,A,B);output out;input A,B;`ifdef add //宏名为addassign out=A+B;`elseassign out=A-B;`endifendmodule【例6.1】加法计数器中的进程module count(data,clk,reset,load,cout,qout);output cout;output[3:0] qout;reg[3:0] qout;input[3:0] data;input clk,reset,load;- 11 - 程序文本always @(posedge clk) //进程1always过程块beginif (!reset) qout= 4'h00; //同步清0低电平有效else if (load) qout= data; //同步预置else qout=qout + 1; //加法计数endassign cout=(qout==4'hf)?1:0; //进程2用持续赋值产生进位信号【例6.2】任务举例module alutask(code,a,b,c);input[1:0] code;input[3:0] a,b;output[4:0] c;reg[4:0] c;task my_and; //任务定义注意无端口列表input[3:0] a,b; //a,b,out名称的作用域范围为task任务内部output[4:0] out;integer i;beginfor(i=3;i>=0;i=i-1)out[i]=a[i]&b[i]; //按位与endendtaskalways@(code or a or b)begincase(code)2'b00: my_and(a,b,c);/* 用任务my_and需注意端口列表的顺序应与任务定义中的一致这里的a,b,c分别对应任务定义中的a,b,out */2'b01: c=a|b; //或2'b10: c=a-b; //相减2'b11: c=a+b; //相加endcaseend- 12 -王金明《Verilog HDL程序设计教程》【例6.3】测试程序`include "alutask.v"module alu_tp;reg[3:0] a,b;reg[1:0] code;wire[4:0] c;parameter DELY = 100;alutask ADD(code,a,b,c); //调用被测试模块initial begincode=4'd0; a= 4'b0000; b= 4'b1111;#DELY code=4'd0; a= 4'b0111; b= 4'b1101;#DELY code=4'd1; a= 4'b0001; b= 4'b0011;#DELY code=4'd2; a= 4'b1001; b= 4'b0011;#DELY code=4'd3; a= 4'b0011; b= 4'b0001;#DELY code=4'd3; a= 4'b0111; b= 4'b1001;#DELY $finish;endinitial $monitor($time,,,"code=%b a=%b b=%b c=%b", code,a,b,c); endmodule【例6.4】函数function[7:0] get0;input[7:0] x;reg[7:0] count;integer i;begincount=0;for (i=0;i<=7;i=i+1)if (x[i]=1'b0) count=count+1;get0=count;endendfunction【例6.5】用函数和case语句描述的编码器不含优先顺序module code_83(din,dout);input[7:0] din;output[2:0] dout;- 13 - 程序文本function[2:0] code; //函数定义input[7:0] din; //函数只有输入输出为函数名本身 casex (din)8'b1xxx_xxxx : code = 3'h7;8'b01xx_xxxx : code = 3'h6;8'b001x_xxxx : code = 3'h5;8'b0001_xxxx : code = 3'h4;8'b0000_1xxx : code = 3'h3;8'b0000_01xx : code = 3'h2;8'b0000_001x : code = 3'h1;8'b0000_000x : code = 3'h0;default: code = 3'hx;endcaseendfunctionassign dout = code(din) ; //函数调用endmodule【例6.6】阶乘运算函数module funct(clk,n,result,reset);output[31:0] result;input[3:0] n;input reset,clk;reg[31:0] result;always @(posedge clk) //在clk的上升沿时执行运算beginif(!reset) result<=0; //复位else beginresult <= 2 * factorial(n); //调用factorial函数endendfunction[31:0] factorial; //阶乘运算函数定义注意无端口列表input[3:0] opa; //函数只能定义输入端输出端口为函数名本身 reg[3:0] i;beginfactorial = opa ? 1 : 0;for(i= 2; i <= opa; i = i+1) //该句若要综合通过opa应赋具体的数值 factorial = i* factorial; //阶乘运算end- 14 -王金明《Verilog HDL程序设计教程》endfunctionendmodule【例6.7】测试程序`define clk_cycle 50`include "funct.v"module funct_tp;reg[3:0] n;reg reset,clk;wire[31:0] result;initial //定义激励向量beginn=0; reset=1; clk=0;for(n=0;n<=15;n=n+1)#100 n=n;endinitial $monitor($time,,,"n=%d result=%d",n,result);//定义输出显示格式always # `clk_cycle clk=~clk; //产生时钟信号funct funct_try(.clk(clk),.n(n),.result(result),.reset(reset)); //调用被测试模块endmodule【例6.8】顺序执行模块1module serial1(q,a,clk);output q,a;input clk;reg q,a;always @(posedge clk)beginq=~q;a=~q;endendmodule【例6.9】顺序执行模块2 module serial2(q,a,clk); output q,a;- 15 - 程序文本input clk;reg q,a;always @(posedge clk)begina=~q;q=~q;endendmodule【例6.10】并行执行模块1 module paral1(q,a,clk);output q,a;input clk;reg q,a;always @(posedge clk)beginq=~q;endalways @(posedge clk)begina=~q;endendmodule【例6.11】并行执行模块2module paral2(q,a,clk);output q,a;input clk;reg q,a;always @(posedge clk)begina=~q;endalways @(posedge clk)beginq=~q;endendmodule【例7.1】调用门元件实现的4选1 MUX- 16 -王金明《Verilog HDL程序设计教程》module mux4_1a(out,in1,in2,in3,in4,cntrl1,cntrl2); output out;input in1,in2,in3,in4,cntrl1,cntrl2;wire notcntrl1,notcntrl2,w,x,y,z;not notcntrl1,cntrl2),(notcntrl2,cntrl2);and (w,in1,notcntrl1,notcntrl2),(x,in2,notcntrl1,cntrl2),(y,in3,cntrl1,notcntrl2),(z,in4,cntrl1,cntrl2);or (out,w,x,y,z);endmodule【例7.2】用case语句描述的4选1 MUXmodule mux4_1b(out,in1,in2,in3,in4,cntrl1,cntrl2); output out;input in1,in2,in3,in4,cntrl1,cntrl2;reg out;always@(in1 or in2 or in3 or in4 or cntrl1 or cntrl2) case({cntrl1,cntrl2})2'b00:out=in1;2'b01:out=in2;2'b10:out=in3;2'b11:out=in4;default:out=2'bx;endcaseendmodule【例7.3】行为描述方式实现的4位计数器module count4(clk,clr,out);input clk,clr;output[3:0] out;reg[3:0] out;always @(posedge clk or posedge clr)beginif (clr) out<=0;else out<=out+1;endendmodule- 17 - 程序文本【例7.4】数据流方式描述的4选1 MUXmodule mux4_1c(out,in1,in2,in3,in4,cntrl1,cntrl2);output out;input in1,in2,in3,in4,cntrl1,cntrl2;assign out=(in1 & ~cntrl1 & ~cntrl2)|(in2 & ~cntrl1 & cntrl2)| (in3 & cntrl1 & ~cntrl2)|(in4 & cntrl1 & cntrl2);endmodule【例7.5】用条件运算符描述的4选1 MUXmodule mux4_1d(out,in1,in2,in3,in4,cntrl1,cntrl2);output out;input in1,in2,in3,in4,cntrl1,cntrl2;assign out=cntrl1 ? (cntrl2 ? in4:in3):(cntrl2 ? in2:in1);endmodule【例7.6】门级结构描述的2选1MUXmodule mux2_1a(out,a,b,sel);output out;input a,b,sel;not (sel_,sel);and a1,a,sel_),(a2,b,sel);or (out,a1,a2);endmodule【例7.7】行为描述的2选1MUXmodule mux2_1b(out,a,b,sel);output out;input a,b,sel;reg out;always @(a or b or sel)beginif(sel) out = b;else out = a;endendmodule【例7.8】数据流描述的2选1MUXmodule MUX2_1c(out,a,b,sel);output out;- 18 -王金明《Verilog HDL程序设计教程》input a,b,sel; assign out = sel ? b : a;endmodule【例7.9】调用门元件实现的1位半加器module half_add1(a,b,sum,cout);input a,b;output sum,cout;and cout,a,b);xor sum,a,b);endmodule【例7.10】数据流方式描述的1位半加器module half_add2(a,b,sum,cout);input a,b;output sum,cout;assign sum=a^b;assign cout=a&b;endmodule【例7.11】采用行为描述的1位半加器module half_add3(a,b,sum,cout);input a,b;output sum,cout;reg sum,cout;always @(a or b)begincase ({a,b}) //真值表描述 2'b00: begin sum=0; cout=0; end2'b01: begin sum=1; cout=0; end2'b10: begin sum=1; cout=0; end2'b11: begin sum=0; cout=1; endendcaseendendmodule【例7.12】采用行为描述的1位半加器module half_add4(a,b,sum,cout);input a,b;output sum,cout;- 19 - 程序文本reg sum,cout;always @(a or b)beginsum= a^b;cout=a&b;endendmodule【例7.13】调用门元件实现的1位全加器 module full_add1(a,b,cin,sum,cout);input a,b,cin;output sum,cout;wire s1,m1,m2,m3;and m1,a,b),(m2,b,cin),(m3,a,cin);xor s1,a,b),(sum,s1,cin);or (cout,m1,m2,m3);endmodule【例7.14】数据流描述的1位全加器module full_add2(a,b,cin,sum,cout);input a,b,cin;output sum,cout;assign sum = a ^ b ^ cin;assign cout = (a & b)|(b & cin)|(cin & a); endmodule【例7.15】1位全加器module full_add3(a,b,cin,sum,cout);input a,b,cin;output sum,cout;assign {cout,sum}=a+b+cin;endmodule【例7.16】行为描述的1位全加器module full_add4(a,b,cin,sum,cout);input a,b,cin;output sum,cout;- 20 -王金明《Verilog HDL程序设计教程》reg sum,cout; //在always块中被赋值的变量应定义为reg型reg m1,m2,m3;always @(a or b or cin)beginsum = (a ^ b) ^ cin;m1 = a & b;m2 = b & cin;m3 = a & cin;cout = (m1|m2)|m3;endendmodule【例7.17】混合描述的1位全加器module full_add5(a,b,cin,sum,cout);input a,b,cin;output sum,cout;reg cout,m1,m2,m3; //在always块中被赋值的变量应定义为reg型wire s1;xor x1(s1,a,b); //调用门元件always @(a or b or cin) //always块语句beginm1 = a & b;m2 = b & cin;m3 = a & cin;cout = (m1| m2) | m3;endassign sum = s1 ^ cin; //assign持续赋值语句endmodule【例7.18】结构描述的4位级连全加器`include "full_add1.v"module add4_1(sum,cout,a,b,cin);output[3:0] sum;output cout;input[3:0] a,b;input cin;full_add1 f0(a[0],b[0],cin,sum[0],cin1); //级连描述full_add1 f1(a[1],b[1],cin1,sum[1],cin2);full_add1 f2(a[2],b[2],cin2,sum[2],cin3);- 21 - 程序文本full_add1 f3(a[3],b[3],cin3,sum[3],cout);endmodule【例7.19】数据流描述的4位全加器module add4_2(cout,sum,a,b,cin);output[3:0] sum;output cout;input[3:0] a,b;input cin;assign {cout,sum}=a+b+cin;endmodule【例7.20】行为描述的4位全加器module add4_3(cout,sum,a,b,cin);output[3:0] sum;output cout;input[3:0] a,b;input cin;reg[3:0] sum;reg cout;always @(a or b or cin)begin{cout,sum}=a+b+cin;endendmodule【例8.1】$time与$realtime的区别`timescale 10ns/1nsmodule time_dif;reg ts;parameter delay=2.6;initialbegin#delay ts=1;#delay ts=0;#delay ts=1;#delay ts=0;endinitial $monitor($time,,,"ts=%b",ts); //使用函数$time- 22 -王金明《Verilog HDL程序设计教程》endmodule【例8.2】$random函数的使用`timescale 10ns/1nsmodule random_tp;integer data;integer i;parameter delay=10;initial $monitor($time,,,"data=%b",data);initial beginfor(i=0; i<=100; i=i+1)#delay data=$random; //每次产生一个随机数 endendmodule【例8.3】1位全加器进位输出UDP元件primitive carry_udp(cout,cin,a,b);input cin,a,b;output cout;table//cin a b : cout //真值表0 0 0 : 0;0 1 0 : 0;0 0 1 : 0;0 1 1 : 1;1 0 0 : 0;1 0 1 : 1;1 1 0 : 1;1 1 1 : 1;endtableendprimitive【例8.4】包含x态输入的1位全加器进位输出UDP元件primitive carry_udpx1(cout,cin,a,b);input cin,a,b;output cout;table// cin a b : cout //真值表0 0 0 : 0;- 23 - 程序文本0 1 0 : 0;0 0 1 : 0;0 1 1 : 1;1 0 0 : 0;1 0 1 : 1;1 1 0 : 1;1 1 1 : 1;0 0 x : 0; //只要有两个输入为0则进位输出肯定为0 0 x 0 : 0;x 0 0 : 0;1 1 x : 1; //只要有两个输入为1则进位输出肯定为1 1 x 1 : 1;x 1 1 : 1;endtableendprimitive【例8.5】用简缩符“”表述的1位全加器进位输出UDP元件 primitive carry_udpx2(cout,cin,a,b);input cin,a,b;output cout;table// cin a b : cout //真值表? 0 0 : 0; //只要有两个输入为0则进位输出肯定为0 0 ? 0 : 0;0 0 ? : 0;? 1 1 : 1; //只要有两个输入为1则进位输出肯定为1 1 ? 1 : 1;1 1 ? : 1;endtableendprimitive【例8.6】3选1多路选择器UDP元件primitive mux31(Y,in0,in1,in2,s2,s1);input in0,in1,in2,s2,s1;output Y;table//in0 in1 in2 s2 s1 : Y0 ? ? 0 0 : 0; //当s2s1=00时Y=in01 ? ? 0 0 : 1;? 0 ? 0 1 : 0; //当s2s1=01时Y=in1- 24 -王金明《Verilog HDL程序设计教程》? 1 ? 0 1 : 1;? ? 0 1 ? : 0; //当s2s1=1时Y=in2? ? 1 1 ? : 1;0 0 ? 0 ? : 0;1 1 ? 0 ? : 1;0 ? 0 ? 0 : 0;1 ? 1 ? 0 : 1;? 0 0 ? 1 : 0;? 1 1 ? 1 : 1;endtableendprimitive【例8.7】电平敏感的1位数据锁存器UDP元件primitive latch(Q,clk,reset,D);input clk,reset,D;output Q;reg Q;initial Q = 1'b1; //初始化table// clk reset D : state : Q? 1 ? : ? : 0 ; //reset=1则不管其他端口为什么值输出都为0 0 0 0 : ? : 0 ; //clk=0锁存器把D端的输入值输出0 0 1 : ? : 1 ;1 0 ? : ? : - ; //clk=1锁存器的输出保持原值用符号“-”表示 endtableendprimitive【例8.8】上升沿触发的D触发器UDP元件primitive DFF(Q,D,clk);output Q;input D,clk;reg Q;table//clk D : state : Q(01) 0 : ? : 0; //上升沿到来输出Q=D(01) 1 : ? : 1;(0x) 1 : 1 : 1;(0x) 0 : 0 : 0;(?0) ? : ? : -; //没有上升沿到来输出Q保持原值? (??) : ? : - ; //时钟不变输出也不变- 25 - 程序文本endtableendprimitive【例8.9】带异步置1和异步清零的上升沿触发的D触发器UDP元件 primitive DFF_UDP(Q,D,clk,clr,set);output Q;input D,clk,clr,set;reg Q;table// clk D clr et state : Q(01) 1 0 0 : ? : 0;(01) 1 0 x : ? : 0;? ? 0 x : 0 : 0;(01) 0 0 0 : ? : 1;(01) 0 x 0 : ? : 1;? ? x 0 : 1 : 1;(x1) 1 0 0 : 0 : 0;(x1) 0 0 0 : 1 : 1;(0x) 1 0 0 : 0 : 0;(0x) 0 0 0 : 1 : 1;? ? 1 ? : ? : 1; //异步复位? ? 0 1 : ? : 0; //异步置1n ? 0 0 : ? : -;? * ? ? : ? : -;? ? (?0) ? : ? : -;? ? ? (?0): ? : -;? ? ? ? : ? : x;endtableendprimitive【例8.12】延迟定义块举例module delay(out,a,b,c);output out;input a,b,c;and a1(n1,a,b);or o1(out,c,n1);specify(a=>out)=2;(b=>out)=3;(c=>out)=1;- 26 -王金明《Verilog HDL程序设计教程》 endspecifyendmodule【例8.13】激励波形的描述'timescale 1ns/1nsmodule test1;reg A,B,C;initialbegin //激励波形描述A = 0;B = 1;C = 0;#100 C = 1;#100 A = 1; B = 0;#100 A = 0;#100 C = 0;#100 $finish;endinitial $monitor($time,,,"A=%d B=%d C=%d",A,B,C); //显示endmodule【例8.15】用always过程块产生两个时钟信号module test2;reg clk1,clk2;parameter CYCLE = 100;alwaysbegin{clk1,clk2} = 2'b10;#(CYCLE/4) {clk1,clk2} = 2'b01;#(CYCLE/4) {clk1,clk2} = 2'b11;#(CYCLE/4) {clk1,clk2} = 2'b00;#(CYCLE/4) {clk1,clk2} = 2'b10;endinitial $monitor($time,,,"clk1=%b clk2=%b",clk1,clk2);endmodule【例8.17】存储器在仿真程序中的应用module ROM(addr,data,oe);output[7:0] data; //数据信号input[14:0] addr; //地址信号input oe; //读使能信号低电平有效- 27 - 程序文本reg[7:0] mem[0:255]; //存储器定义parameter DELAY = 100;assign #DELAY data=(oe==0) ? mem[addr] : 8'hzz;initial $readmemh("rom.hex",mem); //从文件中读入数据 endmodule【例8.18】8位乘法器的仿真程序`timescale 10ns/1nsmodule mult_tp; //测试模块的名字reg[7:0] a,b; //测试输入信号定义为reg型wire [15:0] out; //测试输出信号定义为wire型integer i,j;mult8 m1(out,a,b); //调用测试对象//激励波形设定initialbegina=0;b=0;for(i=1;i<255;i=i+1)#10 a=i;endinitialbeginfor(j=1;j<255;j=j+1)#10 b=j;endinitial //定义结果显示格式begin$monitor($time,,,"%d * %d= %d",a,b,out);#2560 $finish;endendmodulemodule mult8(out, a, b); //8位乘法器源代码parameter size=8;input[size:1] a,b; //两个操作数output[2*size:1] out; //结果assign out=a*b; //乘法运算符- 28 -王金明《Verilog HDL程序设计教程》endmodule 【例8.19】8位加法器的仿真程序`timescale 1ns/1nsmodule add8_tp; //仿真模块无端口列表reg[7:0] A,B; //输入激励信号定义为reg型reg cin;wire[7:0] SUM; //输出信号定义为wire型wire cout;parameter DELY = 100;add8 AD1(SUM,cout,A,B,cin); //调用测试对象initial begin //激励波形设定A= 8'd0; B= 8'd0; cin=1'b0;#DELY A= 8'd100; B= 8'd200; cin=1'b1;#DELY A= 8'd200; B= 8'd88;#DELY A= 8'd210; B= 8'd18; cin=1'b0;#DELY A= 8'd12; B= 8'd12;#DELY A= 8'd100; B= 8'd154;#DELY A= 8'd255; B= 8'd255; cin=1'b1;#DELY $finish;end//输出格式定义initial $monitor($time,,,"%d + %d + %b = {%b, %d}",A,B,cin,cout,SUM);endmodule module add8(SUM,cout,A,B,cin); //待测试的8位加法器模块output[7:0] SUM;output cout;input[7:0] A,B;input cin;assign {cout,SUM}=A+B+cin;endmodule【例8.20】2选1多路选择器的仿真`timescale 1ns/1nsmodule mux_tp;reg a,b,sel;wire out;- 29 - 程序文本MUX2_1 m1(out,a,b,sel); //调用待测试模块initialbegina=1'b0; b=1'b0; sel=1'b0;#5 sel=1'b1;#5 a=1'b1; el=1'b0;#5 sel=1'b1;#5 a=1'b0; b=1'b1; el=1'b0;#5 sel=1'b1;#5 a=1'b1; b=1'b1; sel=1'b0;#5 sel=1'b1;endinitial $monitor($time,,,"a=%b b=%b sel=%b out=%b",a,b,sel,out); endmodulemodule MUX2_1(out,a,b,sel); //待测试的2选1MUX模块input a,b,sel;output out;not #(0.4,0.3) (sel_,sel); //#(0.4,0.3)为门延时and #(0.7,0.6) (a1,a,sel_);and #(0.7,0.6) (a2,b,sel);or #(0.7,0.6) (out,a1,a2);endmodule【例8.21】8位计数器的仿真`timescale 10ns/1nsmodule count8_tp;reg clk,reset; //输入激励信号定义为reg型wire[7:0] qout; //输出信号定义为wire型parameter DELY=100;counter C1(qout,reset,clk); //调用测试对象always #(DELY/2) clk = ~clk; //产生时钟波形initialbegin //激励波形定义clk =0; reset=0;- 30 -王金明《Verilog HDL程序设计教程》#DELY reset=1;#DELY reset=0;#(DELY*300) $finish;end//结果显示initial $monitor($time,,,"clk=%d reset=%d qout=%d",clk,reset,qout);endmodule module counter(qout,reset,clk); //待测试的8位计数器模块output[7:0] qout;input clk,reset;reg[7:0] qout;always @(posedge clk)begin if (reset) qout<=0;else qout<=qout+1;endendmodule【例9.1】基本门电路的几种描述方法1门级结构描述module gate1(F,A,B,C,D);input A,B,C,D;output F;nand(F1,A,B); //调用门元件and(F2,B,C,D);or(F,F1,F2);endmodule2数据流描述module gate2(F,A,B,C,D);input A,B,C,D;output F;assign F=(A&B)|(B&C&D); //assign持续赋值endmodule3行为描述module gate3(F,A,B,C,D);input A,B,C,D;output F;- 31 - 程序文本reg F;always @(A or B or C or D) //过程赋值beginF=(A&B)|(B&C&D);endendmodule【例9.2】用bufif1关键字描述的三态门module tri_1(in,en,out);input in,en;output out;tri out;bufif1 b1(out,in,en); //注意三态门端口的排列顺序endmodule【例9.3】用assign语句描述的三态门module tri_2(out,in,en);output out;input in,en;assign out = en ? in : 'bz;//若en=1则out=in若en=0则out为高阻态 endmodule【例9.4】三态双向驱动器module bidir(tri_inout,out,in,en,b);inout tri_inout;output out;input in,en,b;assign tri_inout = en ? in : 'bz;assign out = tri_inout ^ b;endmodule【例9.5】三态双向驱动器module bidir2(bidir,en,clk);inout[7:0] bidir;input en,clk;reg[7:0] temp;assign bidir= en ? temp : 8'bz;always @(posedge clk)begin- 32 -王金明《Verilog HDL程序设计教程》if(en) temp=bidir;else temp=temp+1;endendmodule【例9.6】3-8译码器module decoder_38(out,in);output[7:0] out;input[2:0] in;reg[7:0] out;always @(in)begincase(in)3'd0: out=8'b11111110;3'd1: out=8'b11111101;3'd2: out=8'b11111011;3'd3: out=8'b11110111;3'd4: out=8'b11101111;3'd5: out=8'b11011111;3'd6: out=8'b10111111;3'd7: out=8'b01111111;endcaseendendmodule【例9.7】8-3优先编码器module encoder8_3(none_on,outcode,a,b,c,d,e,f,g,h); output none_on;output[2:0] outcode;input a,b,c,d,e,f,g,h;reg[3:0] outtemp;assign {none_on,outcode}=outtemp;always @(a or b or c or d or e or f or g or h)beginif(h) outtemp=4'b0111;else if(g) outtemp=4'b0110;else if(f) outtemp=4'b0101;else if(e) outtemp=4'b0100;else if(d) outtemp=4'b0011;else if(c) outtemp=4'b0010;- 33 - 程序文本else if(b) outtemp=4'b0001;else if(a) outtemp=4'b0000;else outtemp=4'b1000;endendmodule【例9.8】用函数定义的8-3优先编码器module code_83(din, dout);input[7:0] din;output[2:0] dout;function[2:0] code; //函数定义input[7:0] din; //函数只有输入端口输出为函数名本身 if (din[7]) code = 3'd7;else if (din[6]) code = 3'd6;else if (din[5]) code = 3'd5;else if (din[4]) code = 3'd4;else if (din[3]) code = 3'd3;else if (din[2]) code = 3'd2;else if (din[1]) code = 3'd1;else code = 3'd0;endfunctionassign dout = code(din); //函数调用endmodule【例9.9】七段数码管译码器module decode47(a,b,c,d,e,f,g,D3,D2,D1,D0);output a,b,c,d,e,f,g;input D3,D2,D1,D0; //输入的4位BCD码reg a,b,c,d,e,f,g;always @(D3 or D2 or D1 or D0)begincase({D3,D2,D1,D0}) //用case语句进行译码 4'd0: {a,b,c,d,e,f,g}=7'b1111110;4'd1: {a,b,c,d,e,f,g}=7'b0110000;4'd2: {a,b,c,d,e,f,g}=7'b1101101;4'd3: {a,b,c,d,e,f,g}=7'b1111001;4'd4: {a,b,c,d,e,f,g}=7'b0110011;4'd5: {a,b,c,d,e,f,g}=7'b1011011;- 34 -王金明《Verilog HDL程序设计教程》4'd6: {a,b,c,d,e,f,g}=7'b1011111;4'd7: {a,b,c,d,e,f,g}=7'b1110000;4'd8: {a,b,c,d,e,f,g}=7'b1111111;。
verilog程序-流水灯
/****************************************************程序功能：流水灯版本：1.1 版权：分享快乐*****************************************************/ module liu_shui_deng(input wire pin_clk_in,input wire pin_rest_n ,input wire [1:0] pin_ctrl,output reg [7:0] pin_led_out);wire clk ;reg [31: 0] counter32;always @ (posedge pin_clk_in or negedge pin_rest_n) begin if(pin_rest_n==1'b0) begincounter32 <= 32'b0;endelse begincounter32 <= counter32+1'b1;endendassign clk = counter32[3] ;reg [2:0] cur_sta,stateparameter [2:0] IDLE =3'b000;parameter [2:0] RIGHT =5'b001;parameter [2:0] LEFT =5'b010;parameter [2:0] DOUB_LEFT =5'b011;parameter [2:0] ERROR =5'b100;always @ (posedge clk or negedge pin_rest_n) beginif(pin_rest_n==1'b0) beginstate <= IDLE ;endelse begincase (state)IDLE : beginif (pin_ctrl==2'b00) beginstate <= LEFT ;endelse if (pin_ctrl==2'b01) beginstate <= RIGHT ;endelse if (pin_ctrl==2'b10) beginendelse beginstate <= ERROR ;endendLEFT : beginif (pin_ctrl==2'b00) beginstate <= LEFT ;endelse if (pin_ctrl==2'b01) begin state <= RIGHT ;endelse if (pin_ctrl==2'b10) begin state <= DOUB_LEFT ;endelse beginstate <= ERROR ;endendRIGHT : beginif (pin_ctrl==2'b00) beginstate <= LEFT ;endelse if (pin_ctrl==2'b01) begin state <= RIGHT ;endelse if (pin_ctrl==2'b10) begin state <= DOUB_LEFT ;endelse beginstate <= ERROR ;endendDOUB_LEFT : beginif (pin_ctrl==2'b00) beginstate <= LEFT ;endelse if (pin_ctrl==2'b01) begin state <= RIGHT ;endelse if (pin_ctrl==2'b10) beginendelse beginstate <= ERROR ;endendERROR : beginif (pin_ctrl==2'b00) beginstate <= LEFT ;endelse if (pin_ctrl==2'b01) beginstate <= RIGHT ;endelse if (pin_ctrl==2'b10) beginstate <= DOUB_LEFT ;endelse beginstate <= ERROR ;endenddefault: state <= IDLE ;endcaseendendalways @ (posedge clk or negedge pin_rest_n) beginif (pin_rest_n == 1'b0) beginpin_led_out[7:0]<=8'b0000_0000 ;endelse begincase (state)IDLE : beginpin_led_out [7:0] <=8'b0000_0000 ;endLEFT : beginif((pin_led_out[0]+pin_led_out[1]+pin_led_out[2]+pin_led_out[3]+pin_led_out[4]+pin_led_out[5]+pin_led_out[6]+pin_led_out[7])!=8'd1 ) beginpin_led_out[7:0] <= 8'b0000_0001;endelse beginpin_led_out[7:1] <= pin_led_out[6:0];pin_led_out[0] <= pin_led_out[7];endendRIGHT : beginif((pin_led_out[0]+pin_led_out[1]+pin_led_out[2]+pin_led_out[3]+pin_led_out[4]+pin_led_out[5]+pin_led_out[6]+pin_led_out[7])!=8'd1 ) beginpin_led_out [7:0] <= 8'b0000_0001 ;endelse beginpin_led_out [6:0] <= pin_led_out [7:1] ;pin_led_out [7] <= pin_led_out [0] ;endendDOUB_LEFT : beginif((pin_led_out[0]+pin_led_out[1]+pin_led_out[2]+pin_led_out[3]+pin_led_out[4]+pin_led_out[5]+pin_led_out[6]+pin_led_out[7])!=8'd2 ) beginpin_led_out [7:0] <= 8'b0000_0011 ;endelse beginpin_led_out [7:1] <= pin_led_out [6:0] ;pin_led_out [0] <= pin_led_out [7] ;endendERROR : beginpin_led_out [7:0]<=8'b1111_1111;enddefault : pin_led_out [7:0] <= 8'b0000_0000;endcaseendendendmodule。
verilog常用系统函数及例子
verilog常⽤系统函数及例⼦1.打开⽂件 integer file_id; file_id = fopen("file_path/file_name");2.写⼊⽂件：$fmonitor,$fwrite,$fdisplay,$fstrobe //$fmonitor只要有变化就⼀直记录 $fmonitor(file_id, "%format_char", parameter); $fmonitor(file_id, "%m: %t in1=%d o1=%h", $time, in1, o1);//$fwrite需要触发条件才记录 $fwrite(file_id, "%format_char", parameter);//$fdisplay需要触发条件才记录 $fdisplay(file_id, "%format_char", parameter);$fstrobe();3.读取⽂件：$fread integer file_id; file_id = $fread("file_path/file_name", "r");4.关闭⽂件：$fclose $fclose(fjile_id);5.由⽂件设定存储器初值：$readmemh，$readmemb $readmemh("file_name", memory_name"); //初始化数据为⼗六进制 $readmemb("file_name", memory_name"); //初始化数据为⼆进制6、⽂件显⽰：$monitor,$write，$display $display,$write⽤于输出信息 $display("rvel = %h hex %d decimal",rvel,rvel); $monitor($time, ,"rxd = %b txd = %b",rxd ,txd)6、⽂件定位 $fseek，⽂件定位，可以从任意点对⽂件进⾏操作； $fscanf，对⽂件⼀⾏进⾏读写。
Verilog电梯程序
module frequence_div(cp_50M,cp_1);input cp_50M;//板子提供的最高时钟output cp_1;//要求得到的秒脉冲reg [27:0] counter_1;//计数器reg cp_1;//类型声明always@(posedge cp_50M)beginif(counter_1==28'h17D7840)//50M的一半到了，秒脉冲翻转begincp_1<=~cp_1;//翻转counter_1<=28'h0000000;endelsecounter_1<=counter_1+1'b1;//否则加1endendmodulemodule elevator_controller(//input ports:cp_50M,clk,reset,forbid,call_up_1, call_up_2, call_up_3,call_up_4, call_up_5,call_down_2, call_down_3, call_down_4,call_down_5,call_down_6,request_1, request_2, request_3,request_4, request_5, request_6,//output ports:out,LiftState,over_alarm,count_out,count);//output ports:output [6:0]out;//输出楼层output [6:0] LiftState;//输出电梯状态output over_alarm;//出错output [6:0]count_out;//计数器输出，便于我控制开关门的状态显示output [2:0]count;//计数器//input ports:input cp_50M;inputclk,reset,call_up_1,call_up_2,call_up_3,call_up_4,call_up_5,call_down_2,call_down_3,call_dow n_4,call_down_5,call_down_6,request_1,request_2,request_3,request_4,request_5,request_6;input forbid;//pos与Posout的关系:当前状态一改变,pos立即作相应改变,而PosOut则是当前状态在要变到下一状态的瞬间//,将PosOut作相应改变。
(EDA技术及应用)第6章VerilogHDL设计应用实例
第6章 Verilog HDL设计应用实例
6.1 8位加法器的设计
1．系统设计思路 加法器是数字系统中的基本逻辑器件，减法器和硬件乘法器 都可由加法器来构成。多位加法器的构成有两种方式：并行进位和 串行进位。并行进位加法器设有进位产生逻辑，运算速度较快；串 行进位方式是将全加器级联构成多位加法器。并行进位加法器通常 比串行级联加法器占用更多的资源。随着位数的增加，相同位数的 并行加法器与串行加法器的资源占用差距也越来越大。因此，在工 程中使用加法器时，要在速度和容量之间寻找平衡点。 实践证明， 4位二进制并行加法器和串行级联加法器占用几乎相 同的资源。这样，多位加法器由 4位二进制并行加法器级联构成是 较好的折中选择。本设计中的8位二进制并行加法器即是由两个4位 二进制并行加法器级联而成的，其电路原理图如图6.1所示。
在掌握了EDA技术的基础知识和基本操作后，学习 EDA技术最有效地方法就是进行EDA技术的综合应用设计 。本章阐述了12个非常实用的Verilog HDL综合应用设计实 例的系统设计思路，主要Verilog HDL源程序，部分时序仿 真和逻辑综合结果及分析，以及硬件的逻辑验证方法。这些 综合应用设计实例包括8位加法器、8位乘法器、8位除法器 等基本运算电路，数字频率计、数字秒表、交通灯信号控制 器、可调信号发生电路、闹钟系统等常用应用电路，PWM 信号发生器、高速PID控制器，FIR滤波器，CORDIC算法 的应用等电机控制、数字信号处理、模糊控制、神经网络中 经常用到的基本电路。
Verilog课程设计_洗衣机设计电路
Verilog课程设计----洗衣机控制器设计要求：设计一个电子定时器，控制洗衣机作如下运转：定时启动--->正转20秒-->暂停10秒-->反转20秒-->暂停10秒-->定时未到，回到“正转20秒-->暂停10秒-->反转20秒-->暂停10秒”；若定时到,则停机发出音响信号。
用两个数码管显示洗涤的预置时间（分钟数），按倒计时的方式计时，直到时间到停机；洗涤过程由“开始”信号开始。
三只LED灯表示“正转”、“反转”、“暂停”三个状态。
设计过程中用三个表示状态的寄存器zz（正转）、fz（反转）、pause（暂停），以及三个寄存器表示LED灯,LED1表示zz；LED2表示fz；LED3表示pause。
用data_out1,data_out2显示预置时间。
Beep为音响信号。
实验源程序如下：`timescale 1ns/1ns //源程序的测试文件module tb_wash;parameter DELY=5;reg clk,start,sure;reg[6:0]count0;wire beep,led1,led2,led3,zz,fz,pause;wire [6:0]data_out1,data_out2;wash C1(data_out1,data_out2,beep,led1,led2,led3,zz,fz,pause,start,count0,sure,clk); initialbeginstart=0;sure=0;count0=7'b0000111;#DELY start=1;#(DELY*10) sure=1;#(DELY*20) sure=0;endalwaysbeginclk=0;#(DELY*2) clk=~clk;#(DELY*2) clk=~clk;//产生振荡时钟endinitial#(DELY*3000)$finish;endmodulemodulewash(data_out1,data_out2,beep,led1,led2,led3,zz,fz,pause,start,count0,sure,clk); input clk,sure;//sure用于输入数据之后的确定键，确定后洗衣机开始工作input[6:0]count0;//count0输入洗涤时间input start;//电源开关output [6:0]data_out1,data_out2;//数码管时间输出reg [6:0]data_out1,data_out2;output zz,fz,pause;reg zz,fz,pause;output led1,led2,led3;reg led1,led2,led3;reg[5:0]counts;output beep; //音响reg beep;reg[6:0]count;//计数分钟reg[3:0]countm;//计数秒wire [3:0]bcd_1;reg [3:0]bcd_2;reg signal;//用于控制音响信号initial begindata_out1=7'b0;data_out2=7'b0;counts<=6'b0;countm<=4'b0;count<=count0;bcd_2<=4'b0;zz<=0;fz<=0;pause<=0;beep<=0;led1<=0;led2<=0;led3<=0;signal<=0;endalways@(posedge clk)beginif(sure==1)beginsignal<=1;count<=count0;//对count赋初值endif((count>0)&&(start==1)&&(signal==1))beginif(counts==6'b111100)//60begincounts<=6'b1;count<=count-1;endelsebegincounts<=counts+1'b1;if(counts<=5'b10100) //20beginzz<=1;fz<=0;pause<=0;led1<=1;led2<=0;led3<=0;endelseif(counts<=6'b11110|counts>6'b110010&&counts<=6'b111011)//30 50~59 beginpause<=1;zz<=0;fz<=0;led2<=1;led1<=0; led3<=0;endelsebeginfz<=1;zz<=0;pause<=0;led3<=1;led1<=0; led2<=0;endendendif(signal==1&&count==0)//控制洗涤结束时音响响的时间beginif(countm==4'b1001)beep<=0;elsebegincountm<=countm+1;beep<=1;led2=0;pause=0;endendend//always//show the numberalways@(count)beginif(count>=7'd90)bcd_2<=4'd9;else if(count>=7'd80)bcd_2<=4'd8;else if(count>=7'd70)bcd_2<=4'd7;else if(count>=7'd60)bcd_2<=4'd6;else if(count>=7'd50)bcd_2<=4'd5;else if(count>=7'd40)bcd_2<=4'd4;else if(count>=7'd30)bcd_2<=4'd3;else if(count>=7'd20)bcd_2<=4'd2;else if(count>=7'd10)bcd_2<=4'd1;elsebcd_2<=4'd0;endassign bcd_1=count-bcd_2*4'd10; always@(bcd_1)//数码管个位的显示begincase (bcd_1)4'b0000:data_out1=7'b0111111;//04'b0001:data_out1=7'b0000110;4'b0010:data_out1=7'b1011011;4'b0011:data_out1=7'b1001111;4'b0100:data_out1=7'b1100110;4'b0101:data_out1=7'b1101101;4'b0110:data_out1=7'b1111100;4'b0111:data_out1=7'b0000111;4'b1000:data_out1=7'b1111111;4'b1001:data_out1=7'b1100111;default:data_out1=7'b0000000;endcaseendalways@(bcd_2)//数码管十位的显示begincase (bcd_2)4'b0000:data_out2=7'b0111111;//04'b0001:data_out2=7'b0000110;4'b0010:data_out2=7'b1011011;4'b0011:data_out2=7'b1001111;4'b0100:data_out2=7'b1100110;4'b0101:data_out2=7'b1101101;4'b0110:data_out2=7'b1111100;4'b0111:data_out2=7'b0000111;4'b1000:data_out2=7'b1111111;4'b1001:data_out2=7'b1100111;default:data_out2=8'b0000000;endcaseendendmodule程序编号之后在linux系统的nclaunch里面仿真出来波形如下：波形符合设计的要求。
Verilog语言编写直流电机控制程序
速度测量模块module Rate_Measure(En,Reset,Rate_Pulse,Measure_Ctrl,Rate_Pulse_Data,Rate_Pulse_Alarm);input En;input Reset;input Rate_Pulse;input Measure_Ctrl;output [15:0] Rate_Pulse_Data;output Rate_Pulse_Alarm;reg [15:0] Rate_Pulse_Data;reg Rate_Pulse_Alarm;wire Counter_Clock;assign Counter_Clock = Measure_Ctrl && Rate_Pulse;always @(posedge Counter_Clock)beginif((En == 1'b1) || (Reset == 1'b1))beginRate_Pulse_Data <= 16'b0;Rate_Pulse_Alarm <= 1'b0;endelsebeginbeginif(Rate_Pulse_Data < 16'b1111111111111111)beginRate_Pulse_Data <= Rate_Pulse_Data + 16'b1;Rate_Pulse_Alarm <= 1'b0;endelsebeginRate_Pulse_Data <= 16'b0;Rate_Pulse_Alarm <= 1'b1;endendendendendmodule速率调整module Rate_Adjust(En,Reset,Rate_Adjust_Select,Rate_Data,Rate_Set,Rate_Adjust_Out);input En;input Reset;input Rate_Adjust_Select;input [15:0] Rate_Data;input [15:0] Rate_Set;output Rate_Adjust_Out;reg Rate_Adjust_Out;always @(En or Reset or Rate_Adjust_Select or Rate_Data or Rate_Set) beginif((En == 1'b1) || (Reset == 1'b1) ||(Rate_Adjust_Select == 1'b0))Rate_Adjust_Out <= 1'b0;elsebeginif(Rate_Data == Rate_Set)Rate_Adjust_Out <= 1'b0;elseRate_Adjust_Out <= 1'b1;endendendmodulemodule Position_Adjust(Reset,En,Position_Adjust_Select,Position_Data,Position_Set,Position_Adjust_Out);input Reset;input En;input Position_Adjust_Select;input [11:0] Position_Data;input [11:0] Position_Set;output Position_Adjust_Out;reg Position_Adjust_Out;always @(En or Reset or Position_Adjust_Select or Position_Data or Position_Set) beginif((En == 1'b1) || (Reset == 1'b1) ||(Position_Adjust_Select == 1'b0))Position_Adjust_Out <= 1'b0;elsebeginif(Position_Data == Position_Set)Position_Adjust_Out <= 1'b0;elsePosition_Adjust_Out <= 1'b1;endendendmodulemodule Position_adc_ctrl( Reset,En,Clk,Adc_Over,Adc_Data,Adc_Cs,Adc_Conv,Adc_Mode,Adc_Rd,Position_Data);input Reset;input En; //En_ininput Clk;input Adc_Over;input [11:0] Adc_Data; //12 bits A/Doutput Adc_Cs;//chip_selectoutput Adc_Conv;//convert_startoutput Adc_Mode;//sleep_modeoutput Adc_Rd;//Read Adc_Dataoutput [11:0] Position_Data;//12 bits positioninteger cnt;reg Adc_Cs;reg Adc_Conv;reg Adc_Mode;reg Adc_Rd;reg [11:0] Position_Data;//12 bits positionalways @(posedge Clk)//always @(En or Reset or Adc_Over or Adc_Data) beginif((Reset == 1'b1) || (En == 1'b1))beginAdc_Cs <= 1'b1;Adc_Conv <= 1'b1;Adc_Mode <= 1'b0;Adc_Rd <= 1'b1;//Position_Data <= 12'b0;endelsebeginAdc_Cs <= 1'b0;Adc_Mode <= 1'b1;if(Adc_Over == 1'b1)//@(negedge Adc_Over)beginAdc_Rd <= 1'b1;Adc_Conv <= 1'b0;end//Adc_Cs <= 1'b0;//Adc_Conv <= 1'b0;//Adc_Mode <= 1'b1;//Adc_Rd <= 1'b1;//if(Adc_Over == 1'b0)//elseif(Adc_Over == 1'b0)beginAdc_Rd <= 1'b0;//Position_Data <= Adc_Data; //Read DataAdc_Conv <= 1'b1;endendalways @(negedge Adc_Rd)beginPosition_Data <= Adc_Data; //Read Dataendendmodulemodule Main_Ctrl(Reset,Position_SW,Rate_SW,Current_SW,Position_En,Rate_En,Current_En,Position_Adjust_En,Rate_Adjust_En,Current_Adjust_En);input Reset;input Position_SW;input Rate_SW;input Current_SW;output Position_En;output Position_Adjust_En;output Rate_En;output Rate_Adjust_En;output Current_En;output Current_Adjust_En;reg Position_En;reg Rate_En;reg Current_En;reg Position_Adjust_En;reg Rate_Adjust_En;reg Current_Adjust_En;always @(Reset or Position_SW or Rate_SW or Current_SW)if(Reset == 1'b1)beginPosition_En <= 1'b1;Position_Adjust_En <= 1'b0;Rate_En <= 1'b1;Rate_Adjust_En <= 1'b0;Current_En <= 1'b1;Current_Adjust_En <= 1'b0;endelsebegincase({Position_SW,Rate_SW,Current_SW})3'b100: beginPosition_En <= 1'b0;Position_Adjust_En <= 1'b1;Rate_En <= 1'b1;Rate_Adjust_En <= 1'b0;Current_En <= 1'b1;Current_Adjust_En <= 1'b0;end3'b010: beginPosition_En <= 1'b1;Position_Adjust_En <= 1'b0;Rate_En <= 1'b0;Rate_Adjust_En <= 1'b1;Current_En <= 1'b1;Current_Adjust_En <= 1'b0;end3'b001: beginPosition_En <= 1'b1;Position_Adjust_En <= 1'b0;Rate_En <= 1'b1;Rate_Adjust_En <= 1'b0;Current_En <= 1'b0;Current_Adjust_En <= 1'b1;end3'b110: beginPosition_En <= 1'b0;Position_Adjust_En <= 1'b1;Rate_En <= 1'b0;Rate_Adjust_En <= 1'b1;Current_En <= 1'b1;Current_Adjust_En <= 1'b0;end3'b101: beginPosition_En <= 1'b0;Position_Adjust_En <= 1'b1;Rate_En <= 1'b1;Rate_Adjust_En <= 1'b0;Current_En <= 1'b0;Current_Adjust_En <= 1'b1;end3'b011: beginPosition_En <= 1'b1;Position_Adjust_En <= 1'b0;Rate_En <= 1'b0;Rate_Adjust_En <= 1'b1;Current_En <= 1'b0;Current_Adjust_En <= 1'b1;end3'b111: beginPosition_En <= 1'b0;Position_Adjust_En <= 1'b1;Rate_En <= 1'b0;Rate_Adjust_En <= 1'b1;Current_En <= 1'b0;Current_Adjust_En <= 1'b1;enddefault:beginPosition_En <= 1'b1;Position_Adjust_En <= 1'b0;Rate_En <= 1'b1;Rate_Adjust_En <= 1'b0;Current_En <= 1'b1;Current_Adjust_En <= 1'b0;endendcaseendendendmodulemodule Data_drive(En,Reset,Clk_SCL,SampleCtrl_in,Adc_Conv,Adc_SCL);input En;input Reset;input Clk_SCL;input SampleCtrl_in;output Adc_Conv;output Adc_SCL;reg Adc_Conv;//reg Adc_SCL;reg [5:0] cnt1;reg Adc_SCL_Select;always @(posedge Clk_SCL) beginif((Reset == 1'b1) || (En == 1'b1)) beginAdc_Conv <= 1'b1;//Adc_SCL <= 1'b0;endelsebeginif(SampleCtrl_in == 1'b1)beginif(cnt1 == 5'b11111)begincnt1 <= 5'b0;Adc_Conv <= 1'b1;Adc_SCL_Select <= 1'b0;endelse if(cnt1 < 5'b01111)begincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b0;Adc_SCL_Select <= 1'b1;endelse if(cnt1 > 5'b11100)begincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b1;Adc_SCL_Select <= 1'b0;endelsebegincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b0;Adc_SCL_Select <= 1'b0;endendendend/*always @(Clk_SCL or Reset or En or SampleCtrl_in or Adc_SCL_Select)beginif((Reset == 1'b1) || (En == 1'b1))begin//Adc_Conv <= 1'b1;Adc_SCL <= 1'b0;endelsebeginif(SampleCtrl_in == 1'b1)beginAdc_SCL <= (Clk_SCL && Adc_Conv);//Adc_Conv <= 1'b0;endelsebegin//Adc_Conv <= 1'b1;Adc_SCL <= 1'b0;endendend*/assign Adc_SCL = Clk_SCL && Adc_SCL_Select;endmodule// Copyright (C) 1991-2004 Altera Corporation// Any megafunction design, and related netlist (encrypted or decrypted),// support information, device programming or simulation file, and any other// associated documentation or information provided by Altera or a partner// under Altera's Megafunction Partnership Program may be used only // to program PLD devices (but not masked PLD devices) from Altera. Any // other use of such megafunction design, netlist, support information,// device programming or simulation file, or any other related documentation// or information is prohibited for any other purpose, including, but not// limited to modification, reverse engineering, de-compiling, or use with// any other silicon devices, unless such use is explicitly licensed under// a separate agreement with Altera or a megafunction partner. Title to the// intellectual property, including patents, copyrights, trademarks, trade// secrets, or maskworks, embodied in any such megafunction design, netlist,// support information, device programming or simulation file, or any other// related documentation or information provided by Altera or a megafunction// partner, remains with Altera, the megafunction partner, or their respective// licensors. No other licenses, including any licenses needed under any third// party's intellectual property, are provided herein.module main(En,Reset,Adc_Busy,Adc_Data,Clk_SCL,Current_Data);input En;input Reset;input Adc_Busy;input Adc_Data;input Clk_SCL;output [11:0] Current_Data;wire SYNTHESIZED_WIRE_0;wire SYNTHESIZED_WIRE_1;Data_drive b2v_inst(.En(En),.Reset(Reset),.Clk_SCL(Clk_SCL),.SampleCtrl_in(SYNTHESIZED_WIRE_0),.Adc_SCL(SYNT HESIZED_WIRE_1));Data_Read b2v_inst1(.En(En),.Reset(Reset),.Adc_Sdata(Adc_Data),.Adc_SCL(SYNTHESIZED_WIRE_1),.Current_Data(Curre nt_Data));Sample_Ctrl b2v_inst2(.En(En),.Reset(Reset),.Adc_Busy(Adc_Busy),.Sample_Ctrl_out(SYNTHESIZED_WIRE_0));Endmodulemodule Data_Read(En,Reset,Adc_Sdata,Adc_SCL,Current_Data);input En;input Reset;input Adc_Sdata;input Adc_SCL;output [11:0] Current_Data;//reg [11:0] Current_Data;reg [3:0] cnt;reg [15:0] Data;always @(negedge Adc_SCL)beginif(cnt <= 4'b1111)beginData[cnt] <= Adc_Sdata;cnt <= cnt + 4'b1;endelsecnt <= 4'b0;endassign Current_Data = Data[15:4];endmodulemodule Position_Adjust(Reset,En,Position_Adjust_Select,Position_Data,Position_Set,Position_Adjust_Out);input Reset;input En;input Position_Adjust_Select;input [11:0] Position_Data;input [11:0] Position_Set;output Position_Adjust_Out;reg Position_Adjust_Out;always @(En or Reset or Position_Adjust_Select or Position_Data or Position_Set) beginif((En == 1'b1) || (Reset == 1'b1) ||(Position_Adjust_Select == 1'b0))Position_Adjust_Out <= 1'b0;elsebeginif(Position_Data == Position_Set)Position_Adjust_Out <= 1'b0;elsePosition_Adjust_Out <= 1'b1;endendendmodulemodule Current_Adjust(En,Reset,Current_Adjust_Select,Current_Data,Current_Set,Current_Adjust_Out);input En;input Reset;input Current_Adjust_Select;input [11:0] Current_Data;input [11:0] Current_Set;output Current_Adjust_Out;reg Current_Adjust_Out;always @(En or Reset or Current_Adjust_Select or Current_Data or Current_Set) beginif((En == 1'b1) || (Reset == 1'b1) ||(Current_Adjust_Select == 1'b0))Current_Adjust_Out <= 1'b0;elsebeginif(Current_Data == Current_Set)Current_Adjust_Out <= 1'b0;elseCurrent_Adjust_Out <= 1'b1;endendendmodulemodule Current_Adjust(En,Reset,Current_Adjust_Select,Current_Data,Current_Set,Current_Adjust_Out);input En;input Reset;input Current_Adjust_Select;input [11:0] Current_Data;input [11:0] Current_Set;output Current_Adjust_Out;reg Current_Adjust_Out;always @(En or Reset or Current_Adjust_Select or Current_Data or Current_Set) beginif((En == 1'b1) || (Reset == 1'b1) ||(Current_Adjust_Select == 1'b0))Current_Adjust_Out <= 1'b0;elsebeginif(Current_Data == Current_Set)Current_Adjust_Out <= 1'b0;elseCurrent_Adjust_Out <= 1'b1;endendendmodulemodule Data_drive(En,Reset,Clk_SCL,SampleCtrl_in,Adc_Conv,Adc_SCL);input En;input Reset;input Clk_SCL;input SampleCtrl_in;output Adc_Conv;output Adc_SCL;reg Adc_Conv;//reg Adc_SCL;reg [5:0] cnt1;reg Adc_SCL_Select;always @(posedge Clk_SCL)beginif((Reset == 1'b1) || (En == 1'b1)) beginAdc_Conv <= 1'b1;//Adc_SCL <= 1'b0;endelsebeginif(SampleCtrl_in == 1'b1)beginif(cnt1 == 5'b11111)begincnt1 <= 5'b0;Adc_Conv <= 1'b1;Adc_SCL_Select <= 1'b0;endelse if(cnt1 < 5'b01111)begincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b0;Adc_SCL_Select <= 1'b1;endelse if(cnt1 > 5'b11100)begincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b1;Adc_SCL_Select <= 1'b0;endelsebegincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b0;Adc_SCL_Select <= 1'b0;endendendend/*always @(Clk_SCL or Reset or En or SampleCtrl_in or Adc_SCL_Select) beginif((Reset == 1'b1) || (En == 1'b1))begin//Adc_Conv <= 1'b1;Adc_SCL <= 1'b0;endelsebeginif(SampleCtrl_in == 1'b1)beginAdc_SCL <= (Clk_SCL && Adc_Conv);//Adc_Conv <= 1'b0;endelsebegin//Adc_Conv <= 1'b1;Adc_SCL <= 1'b0;endendend*/assign Adc_SCL = Clk_SCL && Adc_SCL_Select;endmodulemodule Data_Read(En,Reset,Adc_Sdata,Adc_SCL,Current_Data);input En;input Reset;input Adc_Sdata;input Adc_SCL;output [11:0] Current_Data;//reg [11:0] Current_Data;reg [3:0] cnt;reg [15:0] Data;always @(negedge Adc_SCL)beginif(cnt <= 4'b1111)beginData[cnt] <= Adc_Sdata;cnt <= cnt + 4'b1;endelsecnt <= 4'b0;endassign Current_Data = Data[15:4];endmodulemodule Current_Adjust(En,Reset,Current_Adjust_Select,Current_Data,Current_Set,Current_Adjust_Out);input En;input Reset;input Current_Adjust_Select;input [11:0] Current_Data;input [11:0] Current_Set;output Current_Adjust_Out;reg Current_Adjust_Out;always @(En or Reset or Current_Adjust_Select or Current_Data or Current_Set)beginif((En == 1'b1) || (Reset == 1'b1) ||(Current_Adjust_Select == 1'b0))Current_Adjust_Out <= 1'b0;elsebeginif(Current_Data == Current_Set)Current_Adjust_Out <= 1'b0;elseCurrent_Adjust_Out <= 1'b1;endendendmodulemodule Current_Adjust(En,Reset,Current_Adjust_Select,Current_Data,Current_Set,Current_Adjust_Out);input En;input Reset;input Current_Adjust_Select;input [11:0] Current_Data;input [11:0] Current_Set;output Current_Adjust_Out;reg Current_Adjust_Out;always @(En or Reset or Current_Adjust_Select or Current_Data or Current_Set) beginif((En == 1'b1) || (Reset == 1'b1) ||(Current_Adjust_Select == 1'b0))Current_Adjust_Out <= 1'b0;elsebeginif(Current_Data == Current_Set)Current_Adjust_Out <= 1'b0;elseCurrent_Adjust_Out <= 1'b1;endendendmodulemodule Data_drive(En,Reset,Clk_SCL,SampleCtrl_in,Adc_Conv,Adc_SCL);input En;input Reset;input Clk_SCL;input SampleCtrl_in;output Adc_Conv;output Adc_SCL;reg Adc_Conv;//reg Adc_SCL;reg [5:0] cnt1;reg Adc_SCL_Select;always @(posedge Clk_SCL)beginif((Reset == 1'b1) || (En == 1'b1)) beginAdc_Conv <= 1'b1;//Adc_SCL <= 1'b0;endelsebeginif(SampleCtrl_in == 1'b1)beginif(cnt1 == 5'b11111)begincnt1 <= 5'b0;Adc_Conv <= 1'b1;Adc_SCL_Select <= 1'b0;endelse if(cnt1 < 5'b01111)begincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b0;Adc_SCL_Select <= 1'b1;endelse if(cnt1 > 5'b11100)begincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b1;Adc_SCL_Select <= 1'b0;endelsebegincnt1 <= cnt1 + 5'b1;Adc_Conv <= 1'b0;Adc_SCL_Select <= 1'b0;endendendend/*always @(Clk_SCL or Reset or En or SampleCtrl_in or Adc_SCL_Select) beginif((Reset == 1'b1) || (En == 1'b1))begin//Adc_Conv <= 1'b1;Adc_SCL <= 1'b0;endelsebeginif(SampleCtrl_in == 1'b1)beginAdc_SCL <= (Clk_SCL && Adc_Conv);//Adc_Conv <= 1'b0;endelsebegin//Adc_Conv <= 1'b1;Adc_SCL <= 1'b0;endendend*/assign Adc_SCL = Clk_SCL && Adc_SCL_Select;endmodule。
Verilog_1110010
序列检测器是时序数字电路中非常常见的设计之一。
它的主要功能是将一个指定的序列从数字码流中识别出来。
例如检测器收到一组串行码（1110010）后，输出标志1，否则，输出0。
序列码（1110010）检测器verilog源程序如下`timescale 1ns/100psModule sequence_dectect(in,out,clock,reset);input in,clock,reset;output out;reg[2:0] state;wire out;parameter START=3’b000,A=3’b001,B=3’b010,C=3’b011,D=3’b100,E=3’b101,F=3’b110;assign out=(state==E&&in==0)?1:0;always@(posedge clock or negedge reset)if(!reset)beginstate<=START;endelsecasex(state)START:if(in==1) state=A;A: if(in==0) state<=B;else state<=A;B: if(in==1) state<=C;else state<=A;C: if(in==1) state<=D;else state<=B;D: if(in==1) state<=E;else state<=B;E: if(in==0) state<=F;else state<=A;F: if(in==1) state<=C;else state<=A;default:state=START;endcaseendmodule测试文件`include “sequence_dectect.v”`timescale 1ns/100ps;module test;reg clk,rst;reg[63:0] date;wire out_signal,current_bit;assign current_bit=data[63];initialbeginclk<=0;rst<=1;#2 rst<=0;#30 rst<=1;data=64’b1101_1101_1101_0111_0111_0101_1100_0101_1101_1011_0001_0000_1011_1010_1100_0101;endalways #10 clk=~clk;always@(posedge clk)data<={data[62:0],data[63]};sequence_dectect m(current_bit,out_signal,clk,rst);endmodule。
售货机Verilog程序代码
module autoseller(clk,g,m,yes,read,zero,led_dig,led_seg,led_c,led_r,led); input clk,yes,read,zero;//确定键，商家读取键，清零键input [3:0] g , m; //货品及投币选择键output led_dig,led_seg,led_c,led_r,led;//数码管输出及点阵输出reg f_100;//分频时钟reg f_1;reg [3:0] goods,money,led,change,g_c;integer r,a,b, a_tmp2,a_tmp1;integer ret=0;//用于控制各状态间的转换reg [9:0]count;reg [7:0] led_c,led_r,led_dig,led_seg;reg [1:0]state;integer i;reg x;always @ (posedge clk) //分频模块beginif(a_tmp2==999)beginf_100=~f_100;a_tmp2<=0;endelsea_tmp2<=a_tmp2+1;endalways @ (posedge clk)beginif(a_tmp1==9999999)beginf_1=~f_1;a_tmp1<=0;endelsea_tmp1<=a_tmp1+1;endalways @ (posedge f_1)beginif(ret!=0) //用于按确认键后的计时begina=a+1;endelsebegina=0;endendalways @ (posedge f_100)beginif(zero==0) //清零begincount=0;endif(read!=0) //非商家读取模式（普通读写模式）begin // 识别模块case(g) //表每种货品的拨码开关信号转变为编码4'b0001:begin goods=1;end4'b0010:begin goods=2;end4'b0100:begin goods=5;end4'b1000:begin goods=10;enddefault:begin goods=0;endendcasecase(m) //表每种硬币的拨码开关信号转变为编码4'b0001:begin money=1;end4'b0010:begin money=2;end4'b0100:begin money=5;end4'b1000:begin money=10;enddefault:begin money=0;endendcaseif(a==3) //初始化beginret=0;led=4'b0000;led_c=8'b0000_0000;led_r=8'b1111_1111;x=0;endif(yes==0) //按确定键beginif(money<goods) //金钱不足beginchange=0;ret=1;endelsebegin//金钱足够change=money-goods;ret=2;if(x==0) //交易成功销售总额增加begincount=count+goods;x=1;endendendg_c=goods;//显示模块if(ret==1) //金额不足，数码管报警beginled_c=8'b1111_1111;led_r=8'b0000_0000;endif(ret==2)//交易成功begincase(goods) //LED灯显示货物1:begin led=4'b0001;end2:begin led=4'b0010;end5:begin led=4'b0100;end10:begin led=4'b1000;endendcaseg_c=change;endcase(state)//显示选择的货物0:beginr=g_c % 10;led_dig=8'b1111_1011;case(r)0:begin led_seg=8'b1111_1100;end1:begin led_seg=8'b0110_0000;end2:begin led_seg=8'b1101_1010;end3:begin led_seg=8'b1111_0010;end4:begin led_seg=8'b0110_0110;end5:begin led_seg=8'b1011_0110;end6:begin led_seg=8'b1011_1110;end7:begin led_seg=8'b1110_0000;end8:begin led_seg=8'b1111_1110;end9:begin led_seg=8'b1111_0110;endendcaseend1:beginr=g_c / 10;led_dig=8'b0111_1111;case(r)0:begin led_seg=8'b1111_1100;end1:begin led_seg=8'b0110_0000;end2:begin led_seg=8'b1101_1010;end3:begin led_seg=8'b1111_0010;end4:begin led_seg=8'b0110_0110;end5:begin led_seg=8'b1011_0110;end6:begin led_seg=8'b1011_1110;end7:begin led_seg=8'b1110_0000;end8:begin led_seg=8'b1111_1110;end9:begin led_seg=8'b1111_0110;endendcaseend//显示投入的钱数及余额2:beginr=money % 10;led_dig=8'b1110_1111;case(r)0:begin led_seg=8'b1111_1100;end1:begin led_seg=8'b0110_0000;end2:begin led_seg=8'b1101_1010;end3:begin led_seg=8'b1111_0010;end4:begin led_seg=8'b0110_0110;end5:begin led_seg=8'b1011_0110;end6:begin led_seg=8'b1011_1110;end7:begin led_seg=8'b1110_0000;end8:begin led_seg=8'b1111_1110;end9:begin led_seg=8'b1111_0110;endendcaseend3:beginr=money / 10;led_dig=8'b1111_0111;case(r)0:begin led_seg=8'b1111_1100;end1:begin led_seg=8'b0110_0000;end2:begin led_seg=8'b1101_1010;end3:begin led_seg=8'b1111_0010;end4:begin led_seg=8'b0110_0110;end5:begin led_seg=8'b1011_0110;end6:begin led_seg=8'b1011_1110;end7:begin led_seg=8'b1110_0000;end8:begin led_seg=8'b1111_1110;end9:begin led_seg=8'b1111_0110;endendcaseendcasestate=state+1;endif(read==0)//商家读取模式begincase(i) //显示销售总额0:beginb=count/10;led_dig=8'b1111_1110;case(b)0:begin led_seg=8'b1111_1100;end1:begin led_seg=8'b0110_0000;end2:begin led_seg=8'b1101_1010;end3:begin led_seg=8'b1111_0010;end4:begin led_seg=8'b0110_0110;end5:begin led_seg=8'b1011_0110;end6:begin led_seg=8'b1011_1110;end7:begin led_seg=8'b1110_0000;end8:begin led_seg=8'b1111_1110;end9:begin led_seg=8'b1111_0110;endendcaseend1:beginb=count%10;led_dig=8'b1111_1101;case(b)0:begin led_seg=8'b1111_1100;end1:begin led_seg=8'b0110_0000;end2:begin led_seg=8'b1101_1010;end3:begin led_seg=8'b1111_0010;end4:begin led_seg=8'b0110_0110;end5:begin led_seg=8'b1011_0110;end6:begin led_seg=8'b1011_1110;end7:begin led_seg=8'b1110_0000;end8:begin led_seg=8'b1111_1110;end9:begin led_seg=8'b1111_0110;endendcaseendendcasei=i+1;if(i==2)begini=0;endendendmoduleBCD-LED七段数码显示译码器decode47：module decode47( in, out );input[3:0] in;output[6:0] out;reg[6:0] out;always @( in )begincase(in)4'b0000:out = 7'b1000000;4'b0001:out = 7'b1111001;4'b0010:out = 7'b0100100;4'b0011:out = 7'b0110000;4'b0100:out = 7'b0011001;4'b0101:out = 7'b0010010;4'b0110:out = 7'b0000010;4'b0111:out = 7'b1111000;4'b1000:out = 7'b0000000;4'b1001:out = 7'b0010000;4'b1010:out = 7'b0001000;4'b1011:out = 7'b0000011;4'b1100:out = 7'b1000110;4'b1101:out = 7'b0100001;4'b1110:out = 7'b0000110;4'b1111:out = 7'b0001110;default: out = 7'b0000000;endcaseendendmodule投币输入处理程序key：module key(in,out,clk);input in,clk;output out;reg a,b,out;always @(posedge clk)beginb<=a; //有上升沿来临，输出高电平a<=in;if((a&&(~b))==1)out<=1; else out<=0; end endmodule。
基于FPGA的UART设计的Verilog实现程序
module clkdiv (clk,clkout);input clk; //系统时钟output clkout; //采样时钟输出reg clkout;reg [24:0] cnt;//分频进程always @(posedge clk)beginif(cnt == 24'd162)beginclkout <= 1'b1;cnt <= cnt + 24'd1;endelse if(cnt == 24'd324)beginclkout <= 1'b0;cnt <= 24'd0;endelsebegincnt <= cnt + 24'd1;endendendmodule/*******************发送模块********************************/ module urattx(clk,datain,wrsig,idle,tx);input clk; //UART时钟input [7:0] datain; //需要发送的数据input wrsig; //发送命令，上升沿有效output idle; //线路状态指示，高为线路忙，地为线路空闲output tx; //发送数据信号reg idle,tx;reg send;reg wrsigbuf,wrsigrise;reg presult;reg [7:0] cnt; //计数器parameter paritymode = 1'b0;//检测发送命令是否有效always @(posedge clk)beginwrsigbuf <= wrsig;wrsigrise <=(~wrsigbuf)&wrsig;endalways @(posedge clk)beginif(wrsigrise && (~idle)) //当发送命令有效且线路为空闲时，启动新的数据发送进程beginsend <=1'b1;endelse if(cnt == 8'd176) //一帧资料发送结束beginsend <=1'b0;endendalways @(posedge clk)beginif(send <=1'b1)begincase(cnt)8'd0: //产生起始位begintx <= 1'b0;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd16:begintx <= datain[0]; //发送数据0位presult <= datain[0]^paritymode;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd32:begintx <= datain[1]; //发送数据1位presult <= datain[1]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd48:begintx <= datain[2]; //2presult <= datain[2]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd64:begintx <= datain[3]; //3presult <= datain[3]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd80:begintx <= datain[4]; //4presult <= datain[4]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd96:begintx <= datain[5]; //5presult <= datain[5]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd112:begintx <= datain[6]; //6presult <= datain[6]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd128:begintx <= datain[7]; //7presult <= datain[7]^presult;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd144:begintx <= presult; //发送奇偶校验位presult <= datain[0]^paritymode;idle <= 1'b1;cnt <= cnt + 8'd1;end8'd160:begintx <=1'b1; //发送停止位idle <=1'b1;cnt <=cnt +8'd1;end8'd176:begintx <=1'b1;idle <=1'b0; //一帧资料发送结束cnt <= cnt + 8'd1;enddefault:begincnt<=cnt +8'd1;endendcaseendelsebegintx <= 1'b1;cnt <= 8'd0;idle <=1'b0;endendendmodule。
verilog程序题详解
verilog程序题详解1⽤阻塞⽅式设计⼀个2选1的多路选择器modulemux2_1(ina,inb,sel,out);input ina,inb;input sel;output out;reg out;always@(sel or ina or inb) case(sel)1'b1:out=ina;default:out=inb;endcaseendmodule2 设计⼀个8位全加器moduleadder7(ina,inb,ci,sum,co); input[7:0] ina,inb;input ci;output[7:0]sum;output co;reg[7:0]sum;reg[4:0] carry;genvar i;generate for(i=0;i<4;i=i+1) begin:r_loopalways@(ina[i] or inb[i] or carry[i])begincarry[0]=ci;sum[i]=ina[i]^inb[i]^carry[i]; carry[i+1]=ina[i]&inb[i]|ina[i ]&carry[i]|inb[i]&carry[i]; end endendgenerateassign co=carry[4]; endmodule3 同步复位的4位计数器module count4(clk,nrst,out); input clk,nrst;output[4:0] out;reg[4:0] out;always@(posedge clk) if(!nrst)out<=out+4'b1; endmodule4 ⽤case语句设计⼀个4选1的数据选择器modulemux4_1(en ,in1 ,in2 ,in3 ,in4 ,sel ,out );input en ;input [7:0]in1 ,in2 ,in3 ,in4 ;input [1:0] sel ;output [7:0] out ;reg [7:0] out ;always @(sel or enor in4 or in1 or in2 orin3 )beginif (en == 0) out= {8{1'b0}};elsecase (sel )0 : out = in1 ;1 : out = in2 ;2 : out = in3 ;3 : out = in4 ;default : out ={8{1'b0}};endcaseendendmoduleencoder83(in,outcode); output[2:0] outcode;input [7:0] in;function[2:0] code;input[7:0] ina;if(ina[0])code=3'b000;else if(ina[1]) c ode=3'b001; else if(ina[2]) c ode=3'b010; else if(ina[3]) c ode=3'b011; else if(ina[4]) c ode=3'b100; else if(ina[5])code=3'b101;else if(ina[6]) c ode=3'b110; else if(ina[7]) c ode=3'b111; else code=3'bx; endfunctionassign outcode=code(in); endmodulemodule bianma83(a,b); input [7:0] a;output [2:0] b;reg [2:0] b;always @ (a)begincasex(a)8'b00000001:b=3'b000;8'b0000001x:b=3'b001;8'b000001xx:b=3'b010;8'b00001xxx:b=3'b011;8'b0001xxxx:b=3'b100;8'b001xxxxx:b=3'b101;8'b01xxxxxx:b=3'b110;endcaseendendmodule6.设计⼋功能的算术运算单元(ALU)，其输⼊信号a和b均为4位，功能选择信号select为3位．输出信号out为8位。