Synthesis(怎样写Synthesis)

文章标题：深度剖析Verilog综合成寄存器的写法1. 引言在数字电路设计中，Verilog语言是一种常用的硬件描述语言，可以用来描述电子系统的结构和行为。

在Verilog中，综合（Synthesis）成寄存器的写法是设计中的关键部分之一，本文将深度剖析这一主题，以帮助读者更好地理解Verilog综合的相关知识。

2. Verilog综合概述在Verilog语言中，综合是指将设计描述转换为门级网表的过程。

综合成寄存器是指将Verilog设计语言中的寄存器描述，转换为门级电路中的触发器或锁存器等存储单元。

其写法直接影响着设计的综合结果，因此需要特别注意。

3. Verilog综合成寄存器的基本写法在Verilog中，综合成寄存器的基本写法可以分为两种，分别是使用always块和使用assign语句。

在always块中，通过对时钟边沿进行敏感的触发器描述，可以实现对寄存器的综合。

而使用assign语句则可以直接描述寄存器的逻辑效果，但在综合时需要注意赋值的优先级和逻辑综合后的结果。

4. 深入理解Verilog综合成寄存器的写法在深入理解Verilog综合成寄存器的写法时，需要考虑时序逻辑和组合逻辑的影响。

时序逻辑中常常涉及到时钟、复位等信号的控制，而组合逻辑则更注重通过逻辑门实现的逻辑功能。

在Verilog的编写中，需要根据实际设计需求选择合适的综合成寄存器的写法，并且考虑时序逻辑和组合逻辑之间的交互作用，以实现设计的需求。

5. Verilog综合成寄存器的个人观点和理解在我看来，Verilog综合成寄存器的写法是数字电路设计中非常重要的一环。

正确的写法可以有效地提高设计的性能和可靠性，同时也需要考虑到综合后的电路结构和信号路径。

在Verilog的编写中，需要详细了解每种写法的特性和综合结果，从而做出合适的选择。

6. 结论通过本文的深度剖析，我们对Verilog综合成寄存器的写法有了较为全面的了解。

在实际设计中，需要根据具体的项目需求和目标选择合适的写法，并通过不断实践和调试，提高设计的质量和效率。

图1-14 寄存器输出结构
1-7 什么是基于乘积项的可编程逻辑结构？什么是基于查找表的可编程逻辑 结构？ 答：基于乘积项的可编程结构，即由可编程的“与”阵列和固定的“或”阵 列组成。 可编程的查找表（Look Up Table，LUT）结构，LUT是可编程的最小逻 辑构成单元。大部分FPGA采用基于SRAM（静态随机存储器）的查找表逻 辑形成结构，即用SRAM来构成逻辑函数发生器。一个N输入LUT可以实现N 个输入变量的任何逻辑功能，如N输入“与”、N输入“异或”等。 1-8 就逻辑宏单元而言，GAL中的OLMC、CPLD中的LC、FPGA中的LUT 和LE的含义和结构特点是什么？它们都有何异同点？ 答：输出逻辑宏单元（Output Logic Macro Cell，OLMC），此结构使得 PLD器件在组合逻辑和时序逻辑中的可编程或可重构性能都成为可能。 MAX7000S系列器件包含32~256个逻辑宏单元（Logic Cell，LC），其单个 逻辑宏单元结构如图1-15所示。 LUT即可编程的查找表（Look Up Table，LUT）结构，是可编程的最小逻辑 构成单元。大部分FPGA采用基于SRAM（静态随机存储器）的查找表逻辑 形成结构，即用SRAM来构成逻辑函数发生器。一个N输入LUT可以实现N个 输入变量的任何逻辑功能，如N输入“与”、N输入“异或”等。 LE是Cyclone III FPGA器件的最基本的可编程单元，LE主要由一个4输入的 查找表LUT、进位链逻辑、寄存器链逻辑和一个可编程的寄存器构成。
1-9 为什么说用逻辑门作为衡量逻辑资源大小的最小单元不准确。 答：专业习惯是将OLMC及左侧的可编程与阵列合称一个逻辑宏单元，即标 志PLD器件逻辑资源的最小单元，由此可以认为GAL16V8器件的逻辑资源是 8个逻辑宏单元，而目前最大的FPGA的逻辑资源达数十万个逻辑宏单元。也 有将逻辑门的数量作为衡量逻辑器件资源的最小单元，如某CPLD的资源约 2000门等，但此类划分方法误差较大。

Vivado设计流程一、实验目的与实验要求1、实验目的本实验的目的是熟悉实验环境，学习如何使用Vivado 2015.4创建、综合、实现、仿真等功能。

2、实验要求（1）学习Vivado-Design-Flow.pdf、约束文件.ppt，在实验报告中回答以下问题：a) 描述Vivado 的设计流程b) 什么是网表c) 什么是约束文件？通过IO planning 完成的是什么方面的约束？d) Vivado 设计流程中，Synthesis 的作用是什么？e) Vivado 设计流程中，Implementation 的作用是什么？（2）在实验报告中提交上述实验内容的Verilog 代码、仿真结果图、RTL 详细设计图（参考Vivado-Design-Flow.pdf 第11 页Open Elaborated Design—>Schematic）、综合实现图（参考Vivado-Design-Flow.pdf 第13 页Open Synthesized Design—>Schematic）以及实验现象图（照片）；（3）提交实验报告和完整的工程文件。

二、实验设备（环境）及要求（1）Xilinx Ego1实验平台。

（2）OS：Win7 64位（3）Software：Vivado15.4开发工具三、实验内容与步骤（1）实验内容a)学习视频，了解Vivado设计流程和功能：“EGO五分钟快速上手.mp4”和“EGo五分钟搭建你的数字积木.mp4”。

b)按照“Ego五分钟快速上手——流水灯.pdf”完成流水灯实验。

c)学习Vivado-Design-Flow.pdf、约束文件.ppt，回答问题。

（2）主要步骤a)在Vivado中创建RTL设计，新建一个名为vivado_design_flow的空白工程。

b)模块代码如下：module flowing_light(input clk,input rst,output [15:0] led);reg[23:0]cnt_reg;reg[15:0]light_reg;always@(posedge clk)beginif(rst)cnt_reg<=0;elsecnt_reg<=cnt_reg+1;endalways@(posedge clk)beginif(rst)light_reg<=16'h0001;else if (cnt_reg == 24'hffffff)beginif(light_reg == 16'h8000)light_reg<=16'h0001;elselight_reg<=light_reg<<1;endendassign led = light_reg;endmodulec)RTL门级结构图：图1: RTL门级结构图d)综合Run Synthesis实现图图2：综合最终设计图e)添加约束文件，按照对应管脚，综合、实现进行管脚约束：set_property PACKAGE_PIN F6 [get_ports {led[15]}]set_property PACKAGE_PIN G4 [get_ports {led[14]}]set_property PACKAGE_PIN G3 [get_ports {led[13]}]set_property PACKAGE_PIN J4 [get_ports {led[12]}]set_property PACKAGE_PIN H4 [get_ports {led[11]}]set_property PACKAGE_PIN J3 [get_ports {led[10]}]set_property PACKAGE_PIN J2 [get_ports {led[9]}]set_property PACKAGE_PIN K2 [get_ports {led[8]}]set_property PACKAGE_PIN K1 [get_ports {led[7]}]set_property PACKAGE_PIN H6 [get_ports {led[6]}]set_property PACKAGE_PIN H5 [get_ports {led[5]}]set_property PACKAGE_PIN J5 [get_ports {led[4]}]set_property PACKAGE_PIN K6 [get_ports {led[3]}]set_property PACKAGE_PIN L1 [get_ports {led[2]}]set_property PACKAGE_PIN M1 [get_ports {led[1]}]set_property PACKAGE_PIN K3 [get_ports {led[0]}]set_property PACKAGE_PIN P17 [get_ports clk]set_property PACKAGE_PIN R15 [get_ports rst]set_property IOSTANDARD LVCMOS33 [get_ports {led[15]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[14]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[13]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[12]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[11]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[10]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[9]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[8]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[7]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[6]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[5]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[4]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[3]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[2]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[1]}] set_property IOSTANDARD LVCMOS33 [get_ports {led[0]}] set_property IOSTANDARD LVCMOS33 [get_ports clk]set_property IOSTANDARD LVCMOS33 [get_ports rst]f)测试激励仿真代码：module test( );reg clk;reg rst;wire [3 : 0] led;flowing_light u0(.clk(clk),.rst(rst),.led(led) );parameter PERIOD = 10;always beginclk = 1'b0;#(PERIOD/2) clk = 1'b1;#(PERIOD/2);endinitial beginclk = 1'b0;rst = 1'b0;#100;rst = 1'b1;#100;rst = 1'b0;endendmodule进行行为仿真，得到并验证波形图g)添加时序约束，设置clock的最大和最小的delay timeh)最后进行综合，生成比特流文件，加载到板子上进行调试分析。

Shirley ZhangMr. Michael CrachioloAP Language 216 October 2016Ever since the industrial revolution, science and technology have developed at a high speed and exert a profound and significant impact of people’s lives. The introduction of the steam powered manufacture machine has increased the productivity of industry drastically. The production output gradually fulfills people’s basic needs. However, people’s wants can not be satisfied. In today’s society, people become more materialistic.It is human nature that we do not get satisfied for just getting the basic material for living. According to Henry David Thoreau, after guarantee “the grand necessity—warmth, rich food, houses, clothing,” people will turn to the product that can bring them a higher level of satisfaction—luxury ( Economy P474-476). Luxury can serve as a symbol of middle-class or higher social status and a symbol of identity. Therefore, it is able to provide the processer with the emotional satisfaction he needs. And gradually, people focus their needs for spiritual demand on material things, and thus, become more and more materialistic as the demand increase. As Phyllis Rose suggests “We Americans are beyond a simple, possessive materialism.”The writer points out some interesting phenomena in the article Shopping and Other Spiritual Adventures in America Today that shopping has been functioning as a form of therapy.People nowadays not only go shopping for the material goods, but also use the purchase of those material goods as a way to human communication and connection. The fact that women like to communicate with each other in the dressing room can serve as a great support for this argument (Shopping and Other Spiritual Adventures in America Today P483-484).Some people may hold the opposite of my perspective by saying the prices of the luxury goods have remained constant for years, which indicates that the demand for those goods has remain constant. Based on the statistic of the Forbes Price Index of Luxury Goods, the price change of the luxury goods is insignificant. For instance, the prices of Gucci Loafers, Four Season Hotel, Face-lift, Rolls-Royce Automobile, and Louis Vuitton Duffel bags have remained unchanged from 2009 to 2010 (Forbes Price Index of Luxury Goods P498-499). Those people simply based their opinion on the assumption that the increasing demand will definitely caused the increase of the price. As a matter of fact, the luxury goods can be considered as a special type of product, which suggests that the price of luxury won’t be as flexible as the price of the normal product. In order to maintain the high stander of their brands, they have to keep their price stable. Based on my own observation, more and more people are open to the idea of processing luxury good. And many luxury stores have emerged in the downtown mall for the recent years. All these phenomena indicate the fact that the purchase of the luxury goods has increased.The wants of human are impossible to satisfy. They do not become less urgent the more amply the individual is supplied. According to John Galbraith, “Consumerwants can have bizarre, frivolous or even immoral origins”. And he also indicates the want of the material goods will keep accumulate by quoting the words from Economy Possibilities for Our Grandchildren, “may indeed be insatiable; for the higher the general level, the higher still are they”. Thus, the increasing creation of the material goods can simulate and create “the wants it seek to satisfy” (The Dependence Effect P 478-481). And according to Juliet Schor, the “competitive consumption”can also simulate the want of people. “The competitive consumption is the idea that spending is in large driven by a comparative or competitive process in which individuals try to keep up with the norms of the social group with which they identify”. And the precipitous decline in the savings and the skyrocketed credit card debt both suggest the purchase willingness and the purchase ability have increased (The New Consumerism P 487-488).In conclusion, the wants of human can not be satisfied. The sufficient amount of material goods will simulates the demand for a higher level. In today’s society, people will the guarantee of the basic needs for living are more materialistic, since they require higher level or purchase to satisfy their spiritual needs.Works SiteHenry David Thoreau, EconomyJohn Kenneth Galbraith, The Dependence Effect, The Affluent Society Fortieth Anniversary EditionJ.M. Keynes, Essays in Persuasion, “Economic Possibilities for Our Grandchildren”(London: Macmillan, 1931), p. 365Phyllis Rose, Shopping and Other Spiritual Adventures in America TodayJuliet Schor, The New Consumerism, the Boston ReviewScott DeCarlo, Forbes Price Index of Luxury Goods, the Forbes magazine Wed site, on September 23, 2010。