单片机_电子技术_中英文翻译_毕业论文(6700字)

发表于:2018.3.29来自:www.ttfanwen.com字数:6700 手机看范文

从无线电世界到单片机世界

现代计算机技术的产业革命,将世界经济从资本经济带入到知识经济时代。在电子世界领域,从20世纪中的无线电时代也进入到21世纪以计算机技术为中心的智能化现代电子系统时代。现代电子系统的基本核心是嵌入式计算机系统(简称嵌入式系统),而单片机是最典型、最广泛、最普及的嵌入式系统。

一、 无线电世界造就了几代英才

在20世纪五六十年代,最具代表的先进的电子技术就是无线电技术,包括无线电广播、收音、无线通信(电报)、业余无线电台、无线电定位、导航等遥测、遥控、遥信技术。早期就是这些电子技术带领着许多青少年步入了奇妙的电子世界,无线电技术展示了当时科技生活美妙的前景。电子科学开始形成了一门新兴学科。无线电电子学、无线通信开始了电子世界的历程。

无线电技术不仅成为了当时先进科学技术的代表,而且从普及到专业的科学领域,吸引了广大青少年,并使他们从中找到了无穷的乐趣。从床头的矿石收音机到超外差收音机;从无线电发报到业余无线电台;从电话、电铃到无线电操纵模型。无线电技术成为当时青少年科普、科技教育最普及、最广泛的内容。至今,许多老一辈的工程师、专家、教授当年都是无线电爱好者。无线电技术的无穷乐趣、无线电技术的全面训练,从电子学基本原理、电子元器件基础到无线电遥控、遥测、遥信电子系统制作,培养出了几代科技英才。

二、 从无线电时代到电子技术普及时代

早期的无线电技术推动了电子技术的发展,其中最主要的是真空管电子技术向半导体电子技术的发展。半导体电子技术使有源器件实现了微小型化和低成本,使无线电技术有了更大普及和创新,并大大地开阔了许多非无线电的控制领域。

半导体技术发展导致集成电路器件的产生,形成了近代电子技术的飞跃,电子技术从分立器件时代走进了电路集成时代。电子设计工程师不再用分立的电子元器件设计电路单元,而直接选择集成化的电路单元器件构成系统。他们从电路单元设计中解放出来,致力于系统设计,大大地解放了科技生产力,促进了电子系统更大范围的普及。

半导体集成电路首先在基本数字逻辑电路上取得突破。大量数字逻辑电路,如门电路、计数器、定时器、移位寄存器以及模拟开关、比较器等,为电子数字控制提供了极佳的条件,使传统的机械控制转向电子控制。功率电子器件以及传感技术的发展使原先以无线电为中心的电子技术开始转向工程领域中的机械系统的数字控制,检测领域中的信息采集,运动机械对象的电气伺服驱动控制。

半导体及其集成电路技术将我们带入了一个电子技术普及时代,无线电技术成为电子技术应用领域的一个部分。

进入20世纪70年代,大规模集成电路出现,促进了常规的电子电路单元的专用电子系统发展。许多专用电子系统单元变成了集成化器件,如收音机、电子钟、计算器等,在这些领域的电子工程师从电路、系统的精心设计、调试转变为器件选择、外围器件适配工作。电子技术发展了,电子产品丰富了,电子工程师的难度减少了,但与此同时,无线电技术、电子技术的魅力却削弱了。半导体集成电路的发展使经典电子系统日趋完善,留在大规模集成电路以外的电子技术日益减少,电子技术没有了往昔无线电时代的无穷乐趣和全面的工程训练。

三、 从经典电子技术时代到现代电子技术时代

进入20世纪80年代,世纪经济中最重要的变革是计算机的产业革命。而计算机产业革命的最重要标志则是计算机嵌入式应用的诞生。近代电子计算机是应数值计算要求诞生的。在很长的时间内,电子计算机都是以发展海量数值计算为己任。但是电子计算机表现出的逻辑运算、处理、控制能力,吸引了电子控制领域的专家,他们要求发展能满足控制对象要求,实现嵌入式应用的计算机系统。如果将满足海量数据处理的计算机系统称为通用计算机系统,那么则可把嵌入到对象体系(如舰船、飞机、机车等)中的计算机系统称作嵌入式计算机。显而易见,两者的技术发展方向是不同的。前者要求海量数据存储、吞吐、高速数据处理分析及传输;而后者要求在对象环境中可靠运行,对外部物理参数的高速采集、逻辑分析处理和对外部对象的快速控制等。早期人们将通用计算机加上数据采集单元、输出驱动电路勉为其难地构成一个热处理炉的温控系统。这样的通用计算机系统不可能为大多数电子系统采用,而且要使通用计算机系统满足嵌入式应用要求,必然影响高速数值处理技术的发展。为了解决计算机技术发

展的矛盾,在20世纪70年代,半导体专家另辟蹊径,完全按照电子系统的计算机嵌入式应用要求,将一个微型计算机的基本系统集成在一个芯片上,形成了早期的单片机(Single Chip Microcomputer)。单片机问世后,在计算机领域中开始出现了通用计算机系统和嵌入式系统的两大分支。此后,无论是嵌入式系统,还是通用计算机系统都得到了飞速的发展。

早期虽然有通用计算机改装而成的嵌入式计算机系统,而真正意义上的嵌入式系统始于单片机的出现。因为单片机是专门为嵌入式应用设计的,单片机只能实现嵌入式应用。单片机能最好地满足嵌入式应用的环境要求,例如,芯片级的物理空间、大规模集成电路的低价位、良好的外围接口总线和突出控制功能的指令系统。

单片机有计算机系统内核,嵌入到电子系统中,为电子系统智能化奠定了基础。因此,当前单片机在电子系统中的广泛使用,使经典电子系统迅速过渡到智能化的现代电子系统。

四、 单片机开创了现代电子系统时代

1单片机与嵌入式系统

嵌入式系统源于计算机的嵌入式应用,早期嵌入式系统为通用计算机经改装后嵌入到对象体系中的各种电子系统,如舰船的自动驾驶仪,轮机监测系统等。嵌入式系统首先是一个计算机系统,其次它被嵌入到对象体系中、在对象体系中实现对象要求的数据采集、处理、状态显示、输出控制等功能,由于嵌入在对象体系中,嵌入式系统的计算机没有计算机的独立形式及功能。单片机完全是按照嵌入式系统要求设计的,因此单片机是最典型的嵌入式系统。早期的单片机只是按嵌入式应用技术要求设计的计算机单芯片集成,故名单片机。随后,单片机为满足嵌入式应用要求不断增强其控制功能与外围接口功能,尤其是突出控制功能,因此国际上已将单片机正名为微控制器(MCU,Microcontroller Unit)。

2单片机构成的现代电子系统将成为主流电子系统

单片机是器件级计算机系统,它可以嵌入到任何对象体系中去,实现智能化控制。小到微型机械,如手表、助听器。集成器件级的低价位,低到几元、十几元,足以使单片机普及到许多民用家电、电子玩具中去。单片机构成的现代电子系统已深入到各家各户,正改变我们的生活,如家庭中的音响、电视机、洗衣机、微波炉、电话、防盗系统、空调机等。单片

机革新了原有电子系统,如微波炉采用单片机控制后,可方便地进行时钟设置、程序记忆、功率控制;空调机采用单片机后不但遥控参数设置方便,运行状态自动变换,还可实现变频控制。目前许多家用电器如VCD、DVD只有单片机出现后才可能实现其功能。

3嵌入式系统带动了整个电子产业

目前电子元器件产业除了微处理器、嵌入式系统器件外,大多是围绕现代电子系统配套的元器件产业,例如满足人机交互用的按键,LED/LCD显示驱动、LED/LCD显示单元、语音集成器件等,满足数据采集通道要求的数字传感器、ADC、数据采集模块、信号调理模块等,满足伺服驱动控制的DAC、固体继电器、步进电机控制器、变频控制单元等,满足通信要求的各种总线驱动器、电平转换器等。

世界电子元器件在嵌入式系统带动下,沿着充分满足嵌入式应用的现代电子系统要求发展。这就使原来经典电子系统的天地愈来愈小。电子系统中的各类从业人员应尽早转向现代电子系统的康庄大道。

五、单片机将造就新一代电子精英

如果说五十年代起,无线电世界造就了几代精英,那么当今的单片机世界将会造就出新一代电子精英。

1单片机带你进入智能化电子领域

若将经典电子系统当作一个僵死的电子系统,那么智能化的现代电子系统则是一个具有“生命”的电子系统。单片机应用系统的硬件结构给予电子系统“身躯”,单片机应用系统的应用程序赋予其“生命”。例如,在设计智能化仪器显示器的显示功能时,可在开机时显示系统自检结果,未进入工作时显示各种待机状态,仪器运行时显示运行过程,工作结束后可显示当前结果、自检结果、原始数据、各种处理报表等。在无人值守时,可给定各种自动运行功能。

电子系统的智能化为无止境境界,常常不需硬件资源的增添就能实现各种翻新功能。这也是当前许多家用电器功能大量增设的因素之一。 2单片机带你进入计算机工控领域

21世纪是全人类进入计算机时代的世纪,许多人不是在制造计算机便是在使用计算机。在使用计算机的人们中,只有从事嵌入式系统应用的人才真正地进入到计算机系统的内部软、硬件体系中,才能真正领会计算机

的智能化本质并掌握智能化设计的知识。从学习单片机应用技术入手是当今培养计算机应用软、硬件技术人才的最佳道路之一。

3单片机带你进入最具魅力的电子世界

独具魅力的单片机能使你体会到电脑的真谛,你可以用单片机亲自动手设计智能玩具,可以设计不同的应用程序实现不同的功能。既有硬件制作又有软件设计,既动脑、又动手。初级水平可开发智能玩具,用宏指令编程。中级水平可开发一些智能控制器,如电脑鼠、智能车、各种遥控模型。高级水平可开发机器人,如机器人足球赛,开发工业控制单元,网络通信等,并用汇编语言或高级语言设计应用程序。围绕单片机及嵌入式系统形成的电子产业的未来,将会为电子爱好者提供广阔的天地,一个比当年无线电世界更广阔、更丰富、更持久、更具魅力的电子世界。投身到单片机世界来,将使你一生受益。

单片机攻击技术

目前,攻击单片机主要有四种技术,分别是:

(1)软件攻击

该技术通常使用处理器通信接口并利用协议、加密算法或这些算法中的安全漏洞来进行攻击。软件攻击取得成功的一个典型事例是对早期ATMEL AT89C 系列单片机的攻击。攻击者利用了该系列单片机擦除操作时序设计上的漏洞,使用自编程序在擦除加密锁定位后,停止下一步擦除片内程序存储器数据的操作,从而使加过密的单片机变成没加密的单片机,然后利用编程器读出片内程序。

(2) 电子探测攻击

该技术通常以高时间分辨率来监控处理器在正常操作时所有电源和接口连接的模拟特性,并通过监控它的电磁辐射特性来实施攻击。因为单片机是一个活动的电子器件,当它执行不同的指令时,对应的电源功率消耗也相应变化。这样通过使用特殊的电子测量仪器和数学统计方法分析和检测这些变化,即可获取单片机中的特定关键信息。

(3)过错产生技术

该技术使用异常工作条件来使处理器出错,然后提供额外的访问来进行攻击。使用最广泛的过错产生攻击手段包括电压冲击和时钟冲击。低电压和高电压攻击可用来禁止保护电路工作或强制处理器执行错误操作。时

钟瞬态跳变也许会复位保护电路而不会破坏受保护信息。电源和时钟瞬态跳变可以在某些处理器中影响单条指令的解码和执行。

(4)探针技术

该技术是直接暴露芯片内部连线,然后观察、操控、干扰单片机以达到攻击目的。为了方便起见,人们将以上四种攻击技术分成两类,一类是侵入型攻击(物理攻击),这类攻击需要破坏封装,然后借助半导体测试设备、显微镜和微定位器,在专门的实验室花上几小时甚至几周时间才能完成。所有的微探针技术都属于侵入型攻击。另外三种方法属于非侵入型攻击,被攻击的单片机不会被物理损坏。在某些场合非侵入型攻击是特别危险的,但是因为非侵入型攻击所需设备通常可以自制和升级,因此非常廉价。

大部分非侵入型攻击需要攻击者具备良好的处理器知识和软件知识。与之相反,侵入型的探针攻击则不需要太多的初始知识,而且通常可用一整套相似的技术对付宽范围的产品。

单片机侵入型攻击的一般过程

侵入型攻击的第一步是揭去芯片封装。有两种方法可以达到这一目的:第一种是完全溶解掉芯片封装,暴露金属连线。第二种是只移掉硅核上面的塑料封装。第一种方法需要将芯片绑定到测试夹具上,借助绑定台来操作。第二种方法除了需要具备攻击者一定的知识和必要的技能外,还需要个人的智慧和耐心,但操作起来相对比较方便。

芯片上面的塑料可以用小刀揭开,芯片周围的环氧树脂可以用浓硝酸腐蚀掉。热的浓硝酸会溶解掉芯片封装而不会影响芯片及连线。该过程一般在非常干燥的条件下进行,因为水的存在可能会侵蚀已暴露的铝线连接。

接着在超声池里先用丙酮清洗该芯片以除去残余硝酸,然后用清水清洗以除去盐分并干燥。没有超声池,一般就跳过这一步。这种情况下,芯片表面会有点脏,但是不太影响紫外光对芯片的操作效果。最后一步是寻找保护熔丝的位置并将保护熔丝暴露在紫外光下。一般用一台放大倍数至少100倍的显微镜,从编程电压输入脚的连线跟踪进去,来寻找保护熔丝。若没有显微镜,则采用将芯片的不同部分暴露到紫外光下并观察结果的方式进行简单的搜索。操作时应用不透明的纸片覆盖芯片以保护程序存储器不被紫外光擦除。将保护熔丝暴露在紫外光下5~10分钟就能破坏

掉保护位的保护作用,之后,使用简单的编程器就可直接读出程序存储器的内容。

对于使用了防护层来保护EEPROM单元的单片机来说,使用紫外光复位保护电路是不可行的。对于这种类型的单片机,一般使用微探针技术来读取存储器内容。在芯片封装打开后,将芯片置于显微镜下就能够很容易的找到从存储器连到电路其它部分的数据总线。

由于某种原因,芯片锁定位在编程模式下并不锁定对存储器的访问。利用这一缺陷将探针放在数据线的上面就能读到所有想要的数据。在编程模式下,重启读过程并连接探针到另外的数据线上就可以读出程序和数据存储器中的所有信息。

还有一种可能的攻击手段是借助显微镜和激光切割机等设备来寻找保护熔丝,从而寻查和这部分电路相联系的所有信号线。由于设计有缺陷,因此,只要切断从保护熔丝到其它电路的某一根信号线,就能禁止整个保护功能。由于某种原因,这根线离其它的线非常远,所以使用激光切割机完全可以切断这根线而不影响临近线。这样,使用简单的编程器就能直接读出程序存储器的内容。

虽然大多数普通单片机都具有熔丝烧断保护单片机内代码的功能,但由于通用低档的单片机并非定位于制作安全类产品,因此,它们往往没有提供有针对性的防范措施且安全级别较低。加上单片机应用场合广泛,销售量大,厂商间委托加工与技术转让频繁,大量技术资料外泻,使得利用该类芯片的设计漏洞和厂商的测试接口,并通过修改熔丝保护位等侵入型攻击或非侵入型攻击手段来读取单片机的内部程序变得比较容易。 常用单片机芯片简介

STC单片机

STC公司的单片机主要是基于8051内核,是新一代增强型单片机,指令代码完全兼容传统8051,速度快8~12倍,带ADC,4路PWM,双串口,有全球唯一ID号,加密性好,抗干扰强.

PIC单片机:

是MICROCHIP公司的产品,其突出的特点是体积小,功耗低,精简指令集,抗干扰性好,可靠性高,有较强的模拟接口,代码保密性好,大部分芯片有其兼容的FLASH程序存储器的芯片.

EMC单片机:

是台湾义隆公司的产品,有很大一部分与PIC 8位单片机兼容,且相兼容产品的资源相对比PIC的多,价格便宜,有很多系列可选,但抗干扰较差.

ATMEL单片机(51单片机):

ATMEl公司的8位单片机有AT89、AT90两个系列,AT89系列是8位Flash单片机,与8051系列单片机相兼容,静态时钟模式;AT90系列单片机是增强RISC结构、全静态工作方式、内载在线可编程Flash的单片机,也叫.

PHLIPIS 51PLC系列单片机(51单片机):

PHILIPS公司的单片机是基于80C51内核的单片机,嵌入了掉电检测、模拟以及片内RC振荡器等功能,这使51LPC在高集成度、低成本、低功耗的应用设计中可以满足多方面的性能要求.

HOLTEK单片机:

台湾盛扬半导体的单片机,价格便宜,种类较多,但抗干扰较差,适用于消费类产品.

TI公司单片机(51单片机):

德州仪器提供了TMS370和MSP430两大系列通用单片机.TMS370系列单片机是8位CMOS单片机,具有多种存储模式、多种外围接口模式,适用于复杂的实时控制场合;MSP430系列单片机是一种超低功耗、功能集成度较高的16位低功耗单片机,特别适用于要求功耗低的场合

是台湾松翰公司的单片,大多为8位机,有一部分与PIC 8位单片机兼容,价格便宜,系统时钟分频可选项较多,有PMW ADC 内振 内部杂讯滤波。缺点RAM空间过小,抗干扰较好。




第二篇:单片机技术_中英文翻译_毕业论文[2] 28600字

    本文由xia666724贡献

    doc1。

    从无线电世界到单片机世界化器件,如收音机、电子钟、计算器等, 从无线电世界到单片机世界 在这些领域的电子工程师从电路、系统的精心设计、调试转变为器件选择、 外围器件适配工作。电子技术算机系统称为通用计算机系统,那么则可把 嵌入到对象体系(如舰船 单片机有计算机系统内核,嵌入到电子系统中,为电子系统智能化 奠定了基础。因此,当前单片机在电子系统中的广泛使用,使经典电子系 统迅速过渡到智能化的现代电子系统。 四 、 单片机开创了现代电子系统时代 1 单片机与嵌入式系统 嵌入式系统源于计算机的嵌入式应用,早期嵌入式系统为通用计算机 经改装后嵌入到对象体系中的各种电子系统,如舰船的自动驾驶仪,轮机 监测系统等。嵌入式系统首先是一个计算机系统,其次它被嵌入到对象体 系中、在对象体系中实现对象要求的数据采集、处理、状态显示、输出控 制等功能,由于嵌入在对象体系中,嵌入式系统的计算机没有计算机的独 立形式及功能。单片机完全是按照嵌入式系统要求设计的,因此单片机是 最典型的嵌入式系统。早期的单片机只是按嵌入式应用技术要求设计的计 算机单芯片集成,故名单片机。随后,单片机为满足嵌入式应用要求不断 增强其控制功能与外围接口功能,尤其是突出控制功能,因此国际上已将 单片机正名为微控制器(MCU,Microcontroller Unit)。 2 单片机构成的现代电子系统将成为主流电子系统 单片机是器件级计算机系统,它可以嵌入到任何对象体系中去,实现 智能化控制。小到微型机械,如手表、助听器。集成器件级的低价位,低 到几元、十几元,足以使单片机普及到许多民用家电、电子玩具中去。单 片机构成的现代电子系统已深入到各家各户,正改变我们的生活,如家庭 中的音响、电视机、洗衣机、微波炉、电话、防盗系统、空调机等。单片 机革新了原有电子系统,如微波炉采用单片机控制后,可方便地进行时钟 设置、程序记忆、功率控制;空调机采用单片机后不但遥控参数设置方便, 运行状态自动变换,还可实现变频控制。目前许多家用电器如 VCD、DVD 只有单片机出现后才可能实现其功能。 3 嵌入式系统带动了整个电子产业

    目前电子元器件产业除了微处理器、嵌入式系统器件外,大多是围绕 现代电子系统配套的元器件产业,例如满足人机交互用的按键,LED/LCD 显示驱动、LED/LCD 显示单元、语音集成器件等,满足数据采集通道要求 的数字传感器、ADC、数据采集模块、信号调理模块等,满足伺服驱动控 制的 DAC、固体继电器、步进电机控制器、变频控制单元等,满足通信要 求的各种总线驱动器、电平转换器等。 世界电子元器件在嵌入式系统带动下,沿着充分满足嵌入式应用的现 代电子系统要求发展。这就使原来经典电子系统的天地愈来愈小。电子系 统中的各类从业人员应尽早转向现代电子系统的康庄大道。 五 、 单片机将造就新一代电子精英 如果说五十年代起,无线电世界造就了几代精英,那么当今的单片机 世界将会造就出新一代电子精英。 1 单片机带你进入智能化电子领域 若将经典电子系统当作一个僵死的电子系统,那么智能化的现代电子 系统则是一个具有“生命”的电子系统。 单片机应用系统的硬件结构给予电子 系统“身躯”,单片机应用系统的应用程序赋予其“生命”。例如,在设计智能 化仪器显示器的显示功能时,可在开机时显示系统自检结果,未进入工作 时显示各种待机状态,仪器运行时显示运行过程,工作结束后可显示当前 结果、自检结果、原始数据、各种处理报表等。在无人值守时,可给定各 种自动运行功能。 电子系统的智能化为无止境境界,常常不需硬件资源的增添就能实现 各种翻新功能。这也是当前许多家用电器功能大量增设的因素之一。 2 单片机带你进入计算机工控领域 21 世纪是全人类进入计算机时代的世纪,许多人不是在制造计算机便 是在使用计算机。在使用计算机的人们中,只有从事嵌入式系统应用的人 才真正地进入到计算机系统的内部软、硬件体系中,才能真正领会计算机 的智能化本质并掌握智能化设计的知识。从学习单片机应用技术入手是当 今培养计算机应用软、硬件技术人才的最佳道路之一。 3 单片机带你进入最具魅力的电子世界 独具魅力的单片机能使你体会到电脑的真谛,你可以用单片机亲自动 手设计智能玩具,可以设计不同的应用程序实现不同的功能。既有硬件制

    作又有软件设计,既动脑、又动手。初级水平可开发智能玩具,用宏指令 编程。中级水平可开发一些智能控制器,如电脑鼠、智能车、各种遥控模 型。高级水平可

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开发机器人,如机器人足球赛,开发工业控制单元,网络 通信等,并用汇编语言或高级语言设计应用程序。围绕单片机及嵌入式系 统形成的电子产业的未来,将会为电子爱好者提供广阔的天地,一个比当 年无线电世界更广阔、更丰富、更持久、更具魅力的电子世界。投身到单 片机世界来,将使你一生受益。 单片机攻击技术 目前,攻击单片机主要有四种技术,分别是: ( 1 ) 软件攻击 该技术通常使用处理器通信接口并利用协议、加密算法或这些算法 中的安全漏洞来进行攻击。软件攻击取得成功的一个典型事例是对早期A TMEL AT89C 系列单片机的攻击。攻击者利用了该系列单片机擦 除操作时序设计上的漏洞,使用自编程序在擦除加密锁定位后,停止下一 步擦除片内程序存储器数据的操作,从而使加过密的单片机变成没加密的 单片机,然后利用编程器读出片内程序。 ( 2 ) 电子探测攻击 该技术通常以高时间分辨率来监控处理器在正常操作时所有电源和接 口连接的模拟特性,并通过监控它的电磁辐射特性来实施攻击。因为单片 机是一个活动的电子器件,当它执行不同的指令时,对应的电源功率消耗 也相应变化。这样通过使用特殊的电子测量仪器和数学统计方法分析和检 测这些变化,即可获取单片机中的特定关键信息。 ( 3 ) 过错产生技术 该技术使用异常工作条件来使处理器出错,然后提供额外的访问来进 行攻击。使用最广泛的过错产生攻击手段包括电压冲击和时钟冲击。低电 压和高电压攻击可用来禁止保护电路工作或强制处理器执行错误操作。时 钟瞬态跳变也许会复位保护电路而不会破坏受保护信息。电源和时钟瞬态 跳变可以在某些处理器中影响单条指令的解码和执行。 ( 4 ) 探针技术 该技术是直接暴露芯片内部连线,然后观察、操控、干扰单片机以达 到攻击目的。为了方便起见,人们将以上四种攻击技术分成两类,一类是    侵入型攻击(物理攻击),这类攻击需要破坏封装,然后借助半导体测试 设备、显微镜和微定位器,在专门的实验室花上几小时甚至几周时间才能 完成。所有的微探针技术都属于侵入型攻击。另外三种方法属于非侵入型 攻击,被攻击的单片机不会被物理损坏。在某些场合非侵入型攻击是特别 危险的,但是因为非侵入型攻击所需设备通常可以自制和升级,因此非常 廉价。 大部分非侵入型攻击需要攻击者具备良好的处理器知识和软件知识。 与之相反,侵入型的探针攻击则不需要太多的初始知识,而且通常可用一 整套相似的技术对付宽范围的产品。 单片机侵入型攻击的一般过程 侵入型攻击的第一步是揭去芯片封装。有两种方法可以达到这一目的: 第一种是完全溶解掉芯片封装,暴露金属连线。第二种是只移掉硅核上面 的塑料封装。第一种方法需要将芯片绑定到测试夹具上,借助绑定台来操 作。第二种方法除了需要具备攻击者一定的知识和必要的技能外,还需要 个人的智慧和耐心,但操作起来相对比较方便。 芯片上面的塑料可以用小刀揭开,芯片周围的环氧树脂可以用浓硝酸 腐蚀掉。热的浓硝酸会溶解掉芯片封装而不会影响芯片及连线。该过程一 般在非常干燥的条件下进行,因为水的存在可能会侵蚀已暴露的铝线连接。 接着在超声池里先用丙酮清洗该芯片以除去残余硝酸,然后用清水清 洗以除去盐分并干燥。没有超声池,一般就跳过这一步。这种情况下,芯 片表面会有点脏,但是不太影响紫外光对芯片的操作效果。最后一步是寻 找保护熔丝的位置并将保护熔丝暴露在紫外光下。一般用一台放大倍数至 少100倍的显微镜,从编程电压输入脚的连线跟踪进去,来寻找保护熔 丝。若没有显微镜,则采用将芯片的不同部分暴露到紫外光下并观察结果 的方式进行简单的搜索。操作时应用不透明的纸片覆盖芯片以保护程序存 储器不被紫外光擦除。将保护熔丝暴露在紫外光下5~10分钟就能破坏 掉保护位的保护作用,之后,使用简单的编程器就可直接读出程序存储器 的内容。 对于使用了防护层来保护EEPROM单元的单片机来说,使用紫外 光复位保护电路是不可行的。对于这种类型的单片机,一般使用微探针技

    术来读取存储器内容。在芯片封装打开后,将芯片置于显微镜下就能够很 容易的找到从存储器连到电路其它部分的数据总线。 由于某种原因,芯片锁定位在编程模式下并不锁定对存储器的访问。 利用这一缺陷将探针放在数据线的上面就能读到所有想要的数据。在编程 模式下,重启读过程并连接探针到另外的数据线上就可以读出程序和数据 存储器中的所有信息。 还有一种可能的攻击手段是借助显微镜和激光切割机等设备来寻找保 护熔丝,从而寻查和这部分电路相联系的所有信号线。由于设计有缺陷, 因此,只要切断从保护熔丝到其它电路的某一根信号线,就能禁止整个保 护

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功能。由于某种原因,这根线离其它的线非常远,所以使用激光切割机 完全可以切断这根线而不影响临近线。这样,使用简单的编程器就能直接 读出程序存储器的内容。 虽然大多数普通单片机都具有熔丝烧断保护单片机内代码的功能,但 由于通用低档的单片机并非定位于制作安全类产品,因此,它们往往没有 提供有针对性的防范措施且安全级别较低。加上单片机应用场合广泛,销 售量大,厂商间委托加工与技术转让频繁,大量技术资料外泻,使得利用 该类芯片的设计漏洞和厂商的测试接口,并通过修改熔丝保护位等侵入型 攻击或非侵入型攻击手段来读取单片机的内部程序变得比较容易。 常用单片机芯片简介 STC 单片机 STC 公司的单片机主要是基于 8051 内核,是新一代增强型单片机,指 令代码完全兼容传统 8051,速度快 8 ̄12 倍,带 ADC,4 路 PWM,双串口,有全球 唯一 ID 号,加密性好,抗干扰强. PIC 单片机 : 单片机: 是 MICROCHIP 公司的产品,其突出的特点是体积小,功耗低,精简指 令集,抗干扰性好,可靠性高,有较强的模拟接口,代码保密性好,大部分芯片有 其兼容的 FLASH 程序存储器的芯片. EMC 单片机 : 单片机: 是台湾义隆公司的产品,有很大一部分与 PIC 8 位单片机兼容,且相 兼容产品的资源相对比 PIC 的多,价格便宜,有很多系列可选,但抗干扰较差. 单片机(51 单片机 : 单片机): ATMEL 单片机

    ATMEl 公司的 8 位单片机有 AT89、AT90 两个系列,AT89 系列是 8 位 Flash 单片机,与 8051 系列单片机相兼容,静态时钟模式;AT90 系列单片机是 增强 RISC 结构、全静态工作方式、内载在线可编程 Flash 的单片机,也叫 AVR 单片机. 系列单片机(51 单片机 : 单片机): PHLIPIS 51PLC 系列单片机 PHILIPS 公司的单片机是基于 80C51 内核的单片机,嵌入了掉电检 测、模拟以及片内 RC 振荡器等功能,这使 51LPC 在高集成度、低成本、低 功耗的应用设计中可以满足多方面的性能要求. HOLTEK 单片机 : 单片机: 台湾盛扬半导体的单片机,价格便宜,种类较多,但抗干扰较差,适用于消 费类产品. TI 公司单片机 公司单片机(51 单片机 : 单片机): 德州仪器提供了 TMS370 和 MSP430 两大系列通用单片机.TMS370 系列单片机是 8 位 CMOS 单片机,具有多种存储模式、多种外围接口模式, 适用于复杂的实时控制场合;MSP430 系列单片机是一种超低功耗、功能集 成度较高的 16 位低功耗单片机,特别适用于要求功耗低的场合 是台湾松翰公司的单片,大多为 8 位机,有一部分与 PIC 8 位单片机兼 容,价格便宜,系统时钟分频可选项较多,有 PMW ADC 内振 内部杂讯 滤波。缺点 RAM 空间过小,抗干扰较好。

    From the world of radio in the world to a single chip

    Modern computer technology, industrial revolution, the world economy from the capital into the economy to knowledge economy. Field in the electronic world, from the 20th century into the era of radio to computer technology in the 21st century as the center of the intelligent modern era of electronic systems. The basic core of modern

    electronic systems are embedded computer systems (referred to as embedded systems), while the microcontroller is the most typical and most extensive and most popular embedded systems.

    First, radio has created generations of excellence in the world

    Fifties and sixties in the 20th century, the most representative of the advanced electronic technology is wireless technology, including radio broadcasting, radio, wireless communications (telegraph), Amateur Radio, radio positioning, navigation and other telemetry, remote control, remote technology. Early that these electronic technology led many young people into the wonderful digital world, radio show was a wonderful life, the prospects for science and technology. Electronics began to form a new discipline. Radio electronics, wireless communications began e-world journey. Radio technology not only as a representative of advanced science and technology at that time, but also from popular to professional fields of science, attracting the young people and enable them to find a lot of fun. Ore from the bedside to the superheterodyne radio radio; report issued from the radio amateur radio stations; from the telephone, electric bell to the radio 

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control model. Became popular youth radio technology, science and technology education is the most popular and most extensive content. So far, many of the older generation of engineers, experts, Professor of the year are radio enthusiasts. Fun radio technology, radio technology, comprehensive training, from basic principles of electronics, electronic components to the radio-based remote control, telemetry, remote electronic systems, has trained several generations of technological excellence.

    Second, from the popularity of the radio era to era of electronic technology

    The early radio technology to promote the development of electronic technology, most notably electronic vacuum tube technology to semiconductor electronic technology. Semiconductor technology to realize the active device miniaturization and low cost, so more popular with radio technology and innovation, and to greatly broaden the number of non-radio-control areas. The development of semiconductor technology lead to the production of integrated circuit, forming the modern electronic technology leap from discrete

    electronics into the era of era of integrated circuits. Electronic design engineers no longer use the discrete electronic components designed circuit modules, and direct selection of integrated circuit components constitute a single system. They freed the design of the circuit unit dedicated to system design, greatly liberating the productive forces of science and technology, promote the wider spread of electronic systems. Semiconductor integrated circuits in the basic digital logic circuits first breakthrough. A large number of digital logic circuits, such as gates, counters, timers, shift registers, and analog switches, comparators, etc., for the electronic digital control provides excellent conditions for the traditional mechanical control to electronic control. Power electronic devices and sensor technology to make the original to the radio as the center of electronic technology turned to mechanical engineering in the field of digital control systems, testing in the field of information collection, movement of electrical mechanical servo drive control object. Semiconductor and integrated circuit technology will bring us a universal age of electronic technology, wireless technology as the field of electronic technology a part of. 70 years into the 20th century, large scale integrated circuit appeared to promote the conventional electronic circuit unit-specific electronic systems development. Many electronic systems unit into a dedicated integrated devices such as radios, electronic clocks, calculators, electronic engineers in these areas from the circuit, the system designed to debug into the device selection, peripheral device adapter work. Electronic technology, and electronic products enriched, electronic engineers to reduce the difficulty, but at the same time, radio technology, electronic technology has weakened the charm. The development of semiconductor integrated circuits classical electronic systems are maturing, remain in the large scale integrated circuit other than the shrinking of electronic technology, electronic technology is not the old days of radio fun times and comprehensive engineering training.

    Third, from the classic era of electronic technology to modern electronic technology of the times

    80 years into the 20th century, the century of economic change is the most

    important revolution in the computer. The computer revolution in the 

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most important sign is the birth of the computer embedded applications. Modern computer numerical requirements should be born. A long period of time, is to develop the massive computer numerical duty. But the computer shows the logic operation, processing, control, attracting experts in the field of electronic control, they want development to meet the control object requirements of embedded applications, computer systems. If you meet the massive data-processing computer system known as general-purpose computer system, then the system can be the embedded object (such as ships, aircraft, motorcycles, etc.) in a computer system called the embedded computer. Clearly, both the direction of technology development are different. The former requires massive data storage, handling, processing and analysis of high-speed data transmission; while the latter requires reliable operation in the target environment, the external physical parameters on high-speed acquisition, analysis and processing logic and the rapid control of external objects. It will add an early general-purpose computer data acquisition unit, the output driver circuit reluctance to form a heat treatment furnace temperature control system. This general-purpose computer system is not possible for most of the electronic system used, and to make general-purpose computer system meets the requirements of embedded applications, will inevitably affect the development of high-speed numeric processing. In order to solve the contradiction between the development of computer technology, in the 20th century 70s, semiconductor experts another way, in full accordance with the electronic system embedded computer application requirements, a micro-computer's basic system on a chip, the formation of the early SCM (Single Chip Microcomputer). After the advent of single chip in the computer industry began to appear in the general-purpose computer systems and embedded systems the two branches. Since then, both the embedded system, or general-purpose computer systems have been developed rapidly. Although the early general-purpose computer converted the embedded computer systems, and real embedded system began in the emergence of SCM. Because the microcontroller is designed specifically for embedded applications, the MCU can only achieve embedded applications. MCU embedded applications that best meet environmental requirements, for example, chip-level physical space, large-scale

    integrated circuits low-cost, good peripheral interface bus and outstanding control of instruction. A computer system microcontroller core, embedded electronic systems, intelligent electronic systems for the foundation. Therefore, the current single chip electronic system in widespread use of electronic systems to enable rapid transition to the classical modern intelligent electronic systems.

    4, single chip to create the modern era of electronic systems

    A microcontroller and embedded systems Embedded computer systems from embedded applications, embedded systems for early general-purpose computer adapted to the object system embedded in a variety of electronic systems, such as the ship's autopilot, engine monitoring systems. Embedded system is primarily a computer system, followed by it being embedded into the object system, objects in the object system to achieve required data collection, processing, status display, the output control functions, as embedded in the object system, embedded system computer does not have an independent form and function of the computer. SCM is entirely in accordance with the requirements of embedded system design, so SCM is the most typical embedded systems. SCM is the early application of technical requirements in ac

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cordance with the design of embedded computer chip integration, hence the name single chip. Subsequently, the MCU embedded applications to meet the growing demands of its control functions and peripheral interface functions, in particular, highlight the control function, so has international name the single chip microcontroller (MCU, Microcontroller Unit).

    2 MCU modern electronic systems consisting of electronic systems will become mainstream

    MCU is a device-level computer systems, it can be embedded into any object system to achieve intelligent control. Small to micro-machinery, such as watches, hearing aids. Low-cost integrated device-level, low-to a few dollars, ten dollars, enough to spread to many civilian SCM appliances, electronic toys to go. SCM constitutes a modern electronic systems has in-depth to the households, are changing our lives, such as home audio, televisions, washing machines, microwave ovens, telephones, security systems, and air conditioners. SCM innovation the original

    electronic systems, such as microwave ovens use SCM, it can easily set the clock, the program memory, power control; air conditioner after use of SCM is not only convenient for remote parameter setting, running automatically transform, frequency control can be achieved. At present, many household appliances such as VCD, DVD only single chip to achieve its function may occur before. 3 Embedded Systems led the entire electronics industry Current electronic components industry, in addition to microprocessors, embedded system devices, the most modern electronic systems around the supporting components industries, such as keys used to meet the human-computer interaction, LED / LCD display drivers, LED / LCD display units, voice integrated device, etc., to meet the requirements of data acquisition channel digital sensor, ADC, data acquisition module, signal conditioning modules to meet the servo drive control in the DAC, solid state relays, stepper motor controller, frequency control unit, etc., to meet the communication requirements various bus driver, level converters. Electronic components in the embedded systems world, driven by embedded applications along fully meet requirements of modern electronic systems development. This makes the original classic world of increasingly small electronic systems. Practitioners in the various electronic systems to modern electronic systems as early as possible to stay.

    5, SCM will create a new generation of electronic elite

    If the 50's, radio has created several generations of the world elite, then today's SCM will create a new generation of e-world elite. A single chip with you to the intelligent electronics If we as a dead classic electronic system electronic system, then the intelligent modern electronic systems is a "life" of the electronic system. Application System of hardware, electronic systems, "body", microcontroller applications, the application gives it "life." For example, in the design of intelligent machines monitor display, it can boot the system self-test results show, not to enter the work shows a variety of stand-by state, equipment run-time display running processes, work can be displayed after the end of the current results, self results, raw data, reports and other various processing. Unattended, it can run automatically given a variety of functions.

    Intelligent electronic systems for the endless realm, often without additional hardware resources can achieve all kinds of renovated function. It is also present in many household appliances feature a large number of additional factors. 2 single chip computer with you to the industrial area

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 The 21st century is the century of humanity into the computer age, many people are not used in the manufacture of computer is the computer. People using the computer, only the people engaged in embedded system applications really into the internal computer system hardware and software systems, can we truly understand the nature of the computer's intelligence and grasp the knowledge of intelligent design. MCU applications starting from the learning technology applications in today's computer software training, hardware and technical personnel of one of the best roads. 3 SCM bring you into the most attractive in the digital world Charming single chip to enable you to experience the true meaning of the computer, you can design intelligent microcontroller hands-on toys, different applications can be designed to achieve different functions. Both software design and hardware making there, both mental and physical, but also hands. Primary level can develop intelligent toys, with macro programming. Intermediate levels can develop some intelligent controller, such as computer mouse, smart cars, all kinds of remote control model. High levels can be developed robots, such as robot soccer, the development of industrial control units, network communications, and high-level language with assembly language or design application. Microcontroller and embedded systems around the formation of the future of the electronics industry, will provide a vast world of electronic fans, an even broader than the current wireless world, richer, more durable, more attractive in the digital world. Plunge into the microcontroller in the world to, will benefit your life.

    MCU Attacks

    Currently, there are four single chip attack technique, namely: (1) software attack The technology is commonly used processor communication interface and use protocol, encryption algorithm or the algorithm of security vulnerabilities to attack. The success of software attack is a typical example of the early ATMEL AT89C MCU

    attacks. Attacker single chip erase operation of the timing design flaw, erase the encryption used by ourselves locked in place, the next stop on-chip program memory data erase operation, thus bringing into too close a single chip SCM not encrypted, and then use the programmer to read out chip program. (2) electronic detection of attacks The technology is usually a high time resolution to monitor the processor during normal operation of all power and interface simulation features, and by monitoring the electromagnetic radiation characteristics of it to attack. Because SCM is an active electronic device, when it executes a different command, the corresponding changes in the power consumption accordingly. This through the use of special electronic measuring instruments and mathematical statistical analysis and detection of these changes, you can access key information specific microcontroller. (3) fault generation technology Abnormal working conditions of the technology used to make the processor errors, and provide additional access to attack. Produce the most widely used means of attack, including the fault of the impact and the clock voltage shock. Low voltage and high voltage protection circuit attack can be used to prohibit the work of processor execution errors or enforcement action. Clock transition may reset the transient protection circuit will not damage the protected information. Power and clock transients transition effects in certain single-processor instruction decoding and execution. (4) probe This technology is directly exposed to chip connection, and then observe, manipulate, interfere with single chip to achieve the attack purpose. For convenience, thes

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e four people will attack techniques are divided into two categories is the intrusion type attack (physical attack), such attack requires destruction of package, then use semiconductor test equipment, microscopes and micro-positioning device, in a special laboratory spend hours or even weeks to complete. All of the micro-probe techniques are invasive type attack. The other three methods are non-invasive type attack, attack the MCU will not be physical damage. In some cases, non-invasive-type attacks are particularly dangerous, but because of non-invasive type attacks can

    usually be made and the necessary equipment to upgrade, so it is cheap. Most non-invasive type attack requires the attacker have a good knowledge of processors and software knowledge. In contrast, the invasive type of probe do not need too much of the initial attack of knowledge, and usually a set of similar technology available to deal with a wide range of products

    MCU general process of invasion-type attack

    Invasive type of attack is thrown off its first chip package. There are two ways to achieve this goal: the first one is completely dissolved out chip package, exposed metal connections. The second is only removed to the top of the plastic package silicon core. The first method is the need to bind to the test fixture on the chip, using bind Taiwan to operate. The second method requires the attacker in addition to a certain degree of knowledge and necessary skills, but also the wisdom and patience, but operate relatively easy. Above the plastic chips can be opened with a knife, epoxy around the chip can be eroded by concentrated nitric acid. Hot concentrated nitric acid will dissolve out without affecting the chip, chip packaging and connection. This process usually very dry conditions, because the presence of water may erode the aluminum wire connections have been exposed. Then, in ultrasonic cleaning of the pool first chip with acetone to remove residual nitric acid, then washed with water to remove salt and dried. No ultrasound pool, are generally skip this step. This case, the chip surface, a bit dirty, but do not affect the operation of UV effects on the chip. The final step is to find the location of the protection fuse and fuse protection under exposure to UV light. General use at least a 100 times magnification microscope, from the programming voltage input pin of the connection tracking in, to find protection fuse. If there is no microscope, the use of different parts of the chip is exposed to ultraviolet light and observe the results under the simple search mode. Operation applied opaque paper cover to protect the program memory chips are not erased by ultraviolet light. Will protect the fuse exposed under UV light 5 to 10 minutes to destroy the protection bit of the protective effect, use a simple programmer can directly read the contents of program memory. The use of the protective layer to protect the MCU EEPROM cell, using

    ultraviolet light reset protection circuit is not feasible. For this type of MCU, the general use of micro-probe technology to read the memory contents. In the chip package is opened, the chip placed under the microscope can easily find from the memory circuit connected to other parts of the data bus. For some reason, the chip lock-bit programming mode is not locked in the memory of the visit. Advantage of this flaw on the data lines to probe the above data can be read all you want. In programming mode, restart the process of reading and connect probe to the other data can be read online program and data memory, all of the information. There is also a possible means of attack is the use of microscopy and laser cutting machine

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s and other equipment to find the fuse protection to this part of the circuit tracing and linking all the signal lines. Because of the design defects, so long as cut off from other circuit protection fuse to a one signal line, you can ban the entire protection. For some reason, this thread is very far from the other line, so the use of laser cutting machine can cut the wire without affecting the adjacent line. In this way, using a simple programmer can directly read the contents of program memory. Although the most common single chip microcontroller has fuse blown inside the code protection features, but because of general low-end MCU is not positioning the production of safe products, so they often do not provide targeted preventive measures and the low level of security. MCU applications with a broad, large sales volume, commission processing and transfer of technology between firms frequently spilled a lot of technical data, making use of loopholes in the design of such chips and test interface manufacturer, and by modifying the invasive type fuse protection bits, etc. means of attack or invasion-type attack to read MCU's internal procedures have become easier.    About common single chip

    STC microcontroller STC's mainly based on the 8051 microcontroller core is a new generation of enhanced MCU, the instruction code is fully compatible with the traditional 8051, 8 to 12 times faster, with ADC, 4 Road, PWM, dual serial ports, a global unique ID,

    encryption of good, strong anti-interference. PIC Microcontroller: MICROCHIP's products is its prominent feature is a small, low power consumption, reduced instruction set, interference, reliability, strong analog interface, the code of confidentiality is good, most of the chip has its compatible FLASH program memory chips. EMC SCM: Elan's products in Taiwan, with much of the PIC 8-bit microcontroller compatible, and compatible products, resources, compared to the PIC's more, cheap, there are many series of options, but less interference. ATMEL microcontroller (MCU 51): ATMEl company's 8-bit microcontroller with AT89, AT90 two series, AT89 series is the 8-bit Flash microcontroller 8051 is compatible with the static clock mode; AT90 RISC MCU is to enhance the structure, all static methods of work, containing the line can be Flash MCU programming, also known AVR microcontroller. PHLIPIS 51PLC Microcontroller (MCU 51): PHILIPS company's MCU is based on the 80C51 microcontroller core, embedded power-down detection, simulation and on-chip RC oscillator and other functions, which makes 51LPC in highly integrated, low cost, low power design to meet various applications performance requirements. HOLTEK SCM: Sheng Yang, Taiwan Semiconductor's single chip, cheap more categories, but less interference for consumer products. TI company microcontroller (MCU 51): Texas Instruments MSP430 provides the TMS370 and two series of general-purpose microcontroller. TMS370 MCU is the 8-bit CMOS MCU with a variety of storage mode, a variety of external interface mode, suitable for real-time control of complex situations; MSP430 MCU is a low power, high functionality integrated 16-bit low-power microcontroller, especially for applications that require low power consumption occasions

    Taiwan Sonix's single, mostly 8-bit machines, some with PIC 8-bit microcontroller compatible, cheap, the system clock frequency may be more options there PMW ADC internal noise filtering within the vibration. Shortcomings RAM space is too small, better anti-interference.

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