Lesson 20 Microcontroller Integrated Circuit With Read Only Memory

Transcription

1 Lesson 20 Microcontroller Integrated Circuit With Read Only Memory A microcontroller integrated circuit comprises a processor core which exchanges data with at least one data processing and/or storage device. The integrated circuit comprises a mask-programmed read only memory containing a generic program such as a test program which can be executed by the microcontroller. The generic program includes a basic function for writing data into the data processing and/or storage device or devices. The write function is used to load a downloading program. Because a downloading program is not permanently stored in the read only memory, the microcontroller can be tested independently of the application program, and remains standard with regard to the type of memory component with which it can be used in a system. [1] To be more precise, the invention concerns a microcontroller integrated circuit. A microcontroller is usually a VLSI (Very Large Scale Integration) integrated circuit containing all or most of the components of a "computer". Its function is not predefined but depends on the program that it executes. [2] A microcontroller necessarily comprises a processor core including a command sequencer (which is a device distributing various control signals to the other components according to the instructions of a program), an arithmetic and logic unit (for processing the data) and registers (which are specialized memory units). The other components of the computer can be either internal or external to the microcontroller, however. In other words, the other components are integrated into either the microcontroller or auxiliary circuits. These other components of the "computer" are data processing and/or storage devices, for example read only or random access memory containing the program to be executed, clocks and interfaces (serial or parallel). As a general rule, a system based on a microcontroller therefore comprises a microchip containing the microcontroller, and a plurality of microchips containing the external data processing and/or storage devices which are not integrated into the microcontroller. A microcontroller-based system of this kind comprises, for example, one or more printed circuit boards on which the microcontroller and the other components are mounted. It is the application program, i.e. the program which is executed by the microcontroller, which determines the overall operation of the microcontroller system. Each application program is therefore specific to a separate application. In most current applications the application program is too large to be held in the

2 196 自动化专业英语 microcontroller and is therefore stored in a memory external to the microcontroller. [3] This program memory, which has only to be read, not written, is generally a reprogrammable read only memory (REPROM). After the application program has been programmed in memory and then started in order to be executed by the microcontroller, the microcontroller system may not function as expected. In the least unfavorable situation this is a minor dysfunction of the system and the microcontroller is still able to dialog with a test station via a serial or parallel interface. This test station is then able to determine the nature of the problem and indicate precisely the type of correction (software and/or physical) to be applied to the system for it to operate correctly. Unfortunately, most dysfunctions of a microcontroller-based system result in a total system lock-up, preventing any dialog with a test station. It is then impossible to determine the type of fault, i.e. whether it is a physical fault (in the microcontroller itself, in an external read only memory, in a peripheral device, on a bus, etc) or a software fault (i.e. an error in the application program). [4] The troubleshooting technique usually employed in these cases of total lock-up is based on the use of sophisticated test devices requiring the application of probes to the pins of the various integrated circuits of the microcontroller-based system under test. There are various problems associated with the use of such test devices for troubleshooting a microcontroller-based system. The probes used in these test devices are very fragile, difficult to apply because of the small size of the circuit and their close packing, and may not make good contact with the circuit. Also, because of their high cost, these test devices are not mass produced. Consequently, faulty microcontroller-based systems cannot be repaired immediately, wherever they happen to be located at the time, but must first be returned to a place where a test device is available. Troubleshooting a microcontroller-based system in this way is time-consuming, irksome and costly. To avoid the need for direct action on the microcontroller-based system each time the application program executed by the microcontroller of the system is changed, it is standard practice to use a downloadable read only memory to store the application program, a loading program being written into a mask-programmed read only memory of the microcontroller. The mask-programmed read only memory of the microcontroller is integrated into the microcontroller and programmed once and for all during manufacture of the microcontroller. To change the application program the microcontroller is reset by running the downloading program. This downloading program can then communicate with a workstation connected to the microcontroller by an appropriate transmission line, this workstation containing the new application program to be written into the microcontroller. The downloading program receives the new application program and loads it into a read only memory external to the microcontroller. Although this solution avoids the need for direct action on the microcontroller-based system (which would entail removing from the system the reprogrammable read only memories containing the application program, writing into these memories the new application program 196

3 Lesson 20 Microcontroller Integrated Circuit With Read Only Memory 197 using an appropriate programming device and then replacing them in the system), it nevertheless has a major drawback, namely specialization of the microcontroller during manufacture. Each type of reprogrammable memory is associated with a different downloading program because the programming parameters (voltage to be applied, duration for which the voltage is to be applied, etc) vary with the technology employed. The downloading program is written once and for all into the mask-programmed internal memory of the microcontroller and the latter is therefore restricted to using memory components of the type for which this downloading program was written. In other words, the microcontroller is not a standard component and this increases its cost of manufacture. One object of the invention is to overcome these various drawbacks of the prior art. To be more precise, an object of the invention is to provide a microcontroller circuit which can verify quickly, simply, reliably and at low cost the operation of a system based on the microcontroller. Another object of the invention is to provide a microcontroller integrated circuit which can accurately locate the defective component or components of a system using the microcontroller in the event of dysfunction of the system. A further object of the invention is to provide a microcontroller integrated circuit which avoids the need for direct action on the microcontroller-based system to change the application program, whilst remaining standard as regards the type of memory component with which it can be used in a system. New Words and Phrases 1. auxiliary [ C:^5ziljEri ] adj. 辅助的 2. drawback [ 5drC:7bAk ] n. 缺点障碍 3. dysfunction [ dis5fqnkfen ] n. 官能不良, 官能障碍, 也作 disfunction 4. interface [ 5intE(:)7feis ] n. 接口, 界面, 连接体 [ 装置 ] 5. irksome [ 5E:ksEm ] adj. 令人厌烦的, 令人厌倦的, 令人恼恨的 6. namely [ 5neimli ] adv. 即, 那就是 7. peripheral [ pe5riferel ] adj. 次要的, 外围的 n. 外围设备 8. sequencer [ 5si:kwEnsE ] n. [ 电脑 ] 程序装置, 定序器 9. specialization [ 7speFElai5zeiFEn ] n. 特别化, 专门化 10. troubleshooting n. 疑难排解, 故障诊断 Notes [1] Because a downloading program is not permanently stored in the read only memory, the microcontroller can be tested independently of the application program, and remains standard with regard to the type of memory component with which it can be used in a system. 197

4 198 自动化专业英语 因为装载程序并非永久地存储在只读存储器中, 所以可对单片机进行测试, 而与应用程序无关, 并保持系统中能用的存储器元件为标准类型 句中的 not 起到否定作用, 它的意思是 不 Not 是全部否定, 直接在 be 动词后或引入助动词 do 后加 not 是最简单的否定结构 [2] Its function is not predefined but depends on the program that it executes. 它的功能不是预先确定的, 而是取决于它所执行的程序 句中的 not but 的意思是 不是 而是, 它也是否定结构的一种, 否定 not 后的内容, 肯定 but 后的内容 [3] In most current applications the application program is too large to be held in the microcontroller and is therefore stored in a memory external to the microcontroller. 在多数实际应用中, 由于应用程序太大, 单片机无法存储, 因此就存储在单片机的外部存储器中 句中的 too to 的意思是 太 而不能, 注意 : 它也是否定结构的一种, 尽管它里面不含有明显的否定词 no 或 not 等 [4] It is then impossible to determine the type of fault, i.e. whether it is a physical fault (in the microcontroller itself, in an external read only memory, in a peripheral device, on a bus, etc) or a software fault (i.e. an error in the application program). 这样就不能确定错误类型是硬件错误 ( 单片机本身 外部只读存储器 外围设备 总线等 ) 还是软件错误 ( 应用程序的错误 ) 句中的 impossible 是 possible 加否定前缀 im- 而构成的, 相应的否定前缀还有 ab-,non- 等, 此时还需注意某些词没有否定前后缀但仍表示否定意思, 例如 doubt,wonder Translating Skills 否定结构的翻译 英语中, 有些表示否定意义的特殊结构称作否定结构 如果对这些结构不太熟悉, 会造成误译甚至错译, 翻译时应多加注意 1. Too to 太 不能 结构的翻译 Too to 结构常翻译成 太 不能 ; 如果 too 前加上 not,never,only,all, but 等词, 可译成 并不太 所以能, 表肯定意义 ; 如果在 to 前加 not, 表示 太 而不会不 (1) She is too young to go to school. 他太小, 还不能上学 (2) What he has promised is too good to be true. 他许的诺太好, 恐不可靠 (3) He is too sad not to hold back tears. 他太悲伤, 禁不住流下眼泪 (4) You know but too well to hold your tongue. 你还是闭嘴的好 198

5 Lesson 20 Microcontroller Integrated Circuit With Read Only Memory Unless 结构的翻译 Unless 句型在大多情况下相当于 if not 结构, 翻译为 要是 就不, 除非 等, 这时可与 if not 互换 ; 但在有些虚拟语气的句子中却不能互换 同时还要注意, 当用 unless 时, 较之用 if not 态度要明朗, 语气更有力 (5) The supplier is responsible for the performance of all inspection requirements as specified herein, unless otherwise specified in the contract or purchase order.( 较之用 if not 态度要明朗, 语气更有力, 译作 除非 ) 供货方应负责完成本规范规定的全部检验项目, 除非在合同或订货单上另有规定 (6) You will fail in the exam unless you work harder. ( 可与 if not 互换, 译作 要是 就不 ) 你要是再不努力, 就会考不及格了 (7) Unless bad weather stops me, I go for a walk every day. 除非受阻于坏天气, 我每天都出去散步 (8) I could not expect their help unless they were my friend.( 不可与 if not 互换, 在此的意思是指 我不指望他们的帮助, 但是如果他们是我的朋友, 我会期望他们帮助的 ) 我不能指望他们的帮助, 除非他们是我的朋友 3. Can not too 结构的翻译 can not too 结构是固定结构, 意指 无论如何 也不过分, 有时 cannot 可用 impossible, difficult 等词去替代 ;too 可用 enough,difficulty,sufficiently,exaggerate 等替代 其字面意义与实际意义大不相同, 翻译时首先熟知其结构, 然后正确理解其含义, 再根据汉语习惯辨别是否符合语义逻辑, 就不会闹出笑话 (9) You can t be too careful in exam. 考试时你越仔细越好 (10) We cannot be too careful in entering into a contract with a businessman. 当与商人订立合同时, 你无论如何仔细都不为过 (11) The importance of this discussion cannot be exaggerated. 这次讨论极为重要 (12) You cannot take sufficient care in dealing with such a man. 与这样的人打交道, 你要格外小心 4. No without 结构的翻译 否定词 no,not,never, 等和 without 连用时表示语气很强的否定, 常译作 一 就, 每 必,( 如果 ) 不 / 没有 ( 就 ) 不 / 没有 (13) Without coke iron cannot be smelt. 没有焦炭就不能炼铁 (14) No one thinks of China without thinking of the Great Wall. 人们一想到中国就会想到长城 (15) Neither could theory do without practice, nor could practice do without theory. 199

6 200 自动化专业英语 200 理论没有实践不行, 实践没有理论也不行 (16) She never speaks without smiling. 他一说话就先笑 5. 否定前移结构 由于英汉两种语言的表达习惯的差异, 在表达否定意义时, 英语往往会有否定转移的情况, 而汉语则没有, 因此在英译汉时, 认真分析句子的逻辑和上下文, 掌握常见的否定转移发生的情况, 至关重要 常见的转移方式主要有 : 把否定宾语从句的否定词前移到主句当中 ; 把否定原因状语从句的否定词前移到主句当中 ; 把否定状语的否定词前移到谓语动词前面 ; 把否定主语从句的否定词移到主句当中去 (17) I don t think the novel is worth reading.( 当主句的谓语动词表示意见 想法 希望 假设等意义时, 常把否定宾语从句的否定词转移到主句当中, 这类词有 hope,think,believe, imagine,consider,suppose 等 ) 我认为这本小说不值得一读 (18) He did not travel by air.( 否定介词短语的 not 提到了谓语动词前 ) 他不是乘飞机去旅游的 (19) It is not his thought that you should sign the contract with him.( 否定真正主语从句的 not 提到了句子的表语前 ) 他的看法是你根本不应该和他签订协议 (20) We do not consider melting or boiling to be chemical change.( 否定不定式的 not 提到了谓语动词前 ) 我们认为融化和沸腾不是化学反应 (21) I didn t leave college because I was tired of learning. ( 否定原因状语的 not 放在了谓语动词前, 类似的句式有 not to,not as though,not for 等 但并不是所有的这样的句型都是否定前移, 当 as though, because 引导的从句与主句用逗号隔开时, 或 because 前有 only,simply 修饰时, 不能按否定转移翻译 因此翻译时应根据具体的句内逻辑, 具体对待 ) 我离开了大学, 并不是因为我厌倦了学习 (22) Neutrons carry no charge.( 否定谓语的 no 放在了宾语前 ) 中子不带电荷 (23) He did not do so well as his classmates.( 否定状语的 not 提前放在了谓语动词前 ) 他不像他的同学干得那样好 6. No+ 名词与 not a (an ) + 名词结构的翻译 (24) Not every conclusion can hold water. (not every 表部分否定, 常译为 不是所有都, 并非 等 ) 并非每一结论都站住脚 (25) He was no singer.( 意指 不是的, 表强调 ) 他决不是歌唱家 (26) He is not a singer.

7 Lesson 20 Microcontroller Integrated Circuit With Read Only Memory 201 他不是歌唱家 (27) No machine ever runs without some friction.(no 相当于 not a) 从来没有一台机器运转时没有摩擦 7. No more than 与 not more than 结构的翻译 no more than 常译为 两者都不 ;not more than 常译作 不比 更 如: (28) He is no more a lawyer than a doctor. 它既不是医生也不是律师 (29) He is not more careful than you. 他不比你更细心 8. No more than 与 not more than 结构的翻译 No more than 常译作 只有, 不过, 仅仅 ;not more than 常译作 不超过 如; (30) The coat is no more than $20. 这件大衣只有 20 美元 (31) The machine imported from Japan is not more than $4000. 这台日本进口的机器不超过 4000 美元 9. No less than 与 not less than 结构的翻译 no less than 常译作 竟有 之多, 多达 ;not less than 常译作 不少于, 至少 (32) There were no less than two thousand books in his home. 他家里的藏书竟然多达两千本 (33) There were not less than two thousand books in his home. 他家里的藏书不少于两千本 10. no better than 与 not better than 结构的翻译 no better than 常译作 和 一样不 ;not better than 常译作 并不比 好, 还不如 (34) The computer is no better than that one. 这台电脑和那台差不多 (35) The computer is not better than that one. 这台电脑并不比那台电脑好 Exercise 1. Translate the following into Chinese. (1) I didn t help her because she was rich, or because she was pretty. (2) No man can have too many friends. (3) Its significance and importance can never be overemphasized. 201

8 202 自动化专业英语 2. Translate the following into English. (1) 我坚持认为, 对个人而言, 最重要的莫过于这种根植于个人心灵深处的是非感 (2) 在自然界中不牵涉到两个物体, 就不会有作用力 (3) 引擎并不是因为燃料耗尽停止运转 Reading Material Embedded system In the seventies and eighties of the 20th century, the embedded processor has been used in the fields of industrial control. With the constant growth of the demand for intellectual control of every department, such as industry, health care, and national defence, higher requirements to embedded microprocessor s operation pace, extendible ability, system liability, power consumption and integrated level are needed. In order to meet the needs of various fields, the structure of the embedded microprocessor system has gone through one from CISC to RISC, from 4 bit, 8 bit, 16 bit, 32 bit to 64 bit, can seek address space from 64 KB to more than 16 MB, common encapsulation from 8 feet to 144 feet,processing speed from 0.1 MIPS to 2000 MIPS. The power consumption of the microprocessor has obvious reduced too, its integrated level is further improved, a large amount of SOC (System on Chip ) system emerges. Today, the embedded system has already been applied to fields such as information household appliances, mobile communication, holding information device and industrial control. Foreign famous processor manufacturers (such as Motorola, Intel, AMD, Hitachi, NSC, EPSON ) to introduce each embedded processor one after another, the most representative one is: Motorola company s PowerPC series, Intel company s StrongArm series, AMD company s x86 series, EPSON company s S1C33 series etc. These microprocessors each have their own characteristic, mostly have superior performance, high integrated level, strong extendible ability; they can be applied to all kinds of embedded systems extensively. An embedded system architecture consists of an application-specific hardware part, which interacts with the environment. At the same time, an application specific software part runs on a microcontroller. The embedded system s final purpose is application. It is based on computer technology, its software and hardware can be disposed and it is an application-specific system which has a strong restrict to the function, cost, volume, power consumption, so the computers used are called the embedded computer. This kind of system is generally made up of embedded microprocessor, peripheral hardware device, embedded operating system and application program so as to control, monitor and manage other device. The structure of the system varies with the application; it can be inlaid and buried in the application device or system in the form of single-board, body of case or distributed joint etc. In essence, the computer in the embedded system is always in a kind of real-time calculation mode, we can think that the embedded computer should have a certain real-time characteristic. In other words, there are some inherent connections between the embedded application and real-time application of the computer, 202

9 Lesson 20 Microcontroller Integrated Circuit With Read Only Memory 203 according to the attribute on which the application emphasizes. This kind of computer application system can be called embedded system, real-time system or embedded real-time system. Most real-time systems are all embedded application. The computer is a kind of intellectual part which install inside of the system which has great response speed, the main function is as the information processing part in a large-scale project system.in this case, users do not need to know that there is existence of the computer in the device, generally,it can t be programmed by users. It has some application-specific I/O device and interface. So, the embedded software are developed through cross-develop, development environment is different from real-time environment. Compared with general-purpose computer, the embedded system have many characteristics such as: respond in time, parallel processing, application-specific and compact, skill-intensive, difficult to develop, variety,etc. New words and phrases 1. application-specific adj. 专用的 2. extendible [ik5stendeb(e)l] adj. 可延长的, 可扩张的 3. inlaid [5in5leid] adj. 镶嵌的, 镶饰的 4. representative [7repri5zentEtiv] adj. 代表性的, 典型的 203