精品中英文外文翻译--PLC和微处理器-定
PLC中英文资料外文翻译
附录外文资料PLC technique discussion and future development Along with the development of the ages, the technique that is nowadays is also gradually perfect, the competition plays more more strong; the operation that list depends the artificial has already can't satisfied with the current manufacturing industry foreground, also can't guarantee the request of the higher quantity and high new the image of the technique business enterprise.The people see in produce practice, automate brought the tremendous convenience and the product quantities for people up of assurance, also eased the personnel's labor strength, reduce the establishment on the personnel. The target control of the hard realization in many complicated production lines, whole and excellent turn, the best decision etc., well-trained operation work, technical personnel or expert, governor but can judge and operate easily, can acquire the satisfied result. The research target of the artificial intelligence makes use of the calculator exactly to carry out, imitate these intelligences behavior, moderating the work through person's brain and calculators, with the mode that person's machine combine, for resolve the very complicated problem to look for the best pathWe come in sight of the control that links after the electric appliances in various situation, that is already the that time generation past, now of after use in the mold a perhaps simple equipments of grass-roots control that the electric appliances can do for the low level only;And the PLC emergence also became the epoch-making topic, adding the vivid software control through a very and stable hardware, making the automation head for the new high tide.The PLC biggest characteristics lie in: The electrical engineering teacher already no longer electric hardware up too many calculationses of cost, as long as order the importation that the button switch or the importation of the sensors order to link the PLC up can solve problem, pass to output to order the conjunction contact machine or control the start equipments of the big power after the electric appliances, but theexportation equipments direct conjunction of the small power can.PLC internal containment have the CPU of the CPU, and take to have an I/ O for expand of exterior to connect a people's address and saving machine three big pieces to constitute, CPU core is from an or many is tired to add the machine to constitute, mathematics that they have the logic operation ability, and can read the procedure save the contents of the machine to drive the homologous saving machine and I/ Os to connect after pass the calculation; The I/ O add inner part is tired the input and output system of the machine and exterior link, and deposit the related data into the procedure saving machine or data saving machine; The saving machine can deposit the data that the I/ O input in the saving machine, and in work adjusting to become tired to add the machine and I/ Os to connect, saving machine separately saving machine RAM of the procedure saving machine ROM and datas, the ROM can can do deposit of the data permanence in the saving machine, but RAM only for the CPU computes the temporary calculation usage of hour of buffer space.The PLC anti- interference is very and excellent, our root need not concern its service life and the work situation bad, these all problems have already no longer become the topic that we fail, but stay to our is a concern to come to internal resources of make use of the PLC to strengthen the control ability of the equipments for us, make our equipments more gentle.PLC language is not we imagine of edit collected materials the language or language of Cs to carry on weaving the distance, but the trapezoid diagram that the adoption is original after the electric appliances to control, make the electrical engineering teacher while weaving to write the procedure very easy comprehended the PLC language, and a lot of non- electricity professional also very quickly know and go deep into to the PLC.Is PLC one of the advantage above and only, this is also one part that the people comprehend more and easily, in a lot of equipmentses, the people have already no longer hoped to see too many control buttons, they damage not only and easily and produce the artificial error easiest, small is not a main error perhaps you can still accept; But lead even is a fatal error greatly is what we can't is tolerant of. Newtechnique always for bringing more safe and convenient operation for us, make we a lot of problems for face on sweep but light, do you understand the HMI? Says the HMI here you basically not clear what it is, also have no interest understanding, change one inside text explains it into the touch to hold or man-machine interface you knew, it combines with the PLC to our larger space.HMI the control not only only is reduced the control press button, increase the vivid of the control, more main of it is can sequence of, and at can the change data input to output the feedback with data, control in the temperature curve of imitate but also can keep the manifestation of view to come out. And can write the function help procedure through a plait to provide the help of various what lies in one's power, the one who make operate reduces the otiose error. Currently the HMI factory is also more and more, the function is also more and more strong, the price is also more and more low, the noodles of the usage are wide more and more. The HMI foreground can say that think ° to be good very.At a lot of situations, the list is is a smooth movement that can't guarantee the equipments by the control of the single machine, but pass the information exchanges of the equipments and equipments to attain the result that we want. For example fore pack and the examination of the empress work preface, we will arrive wrapping information feedback to examine the place, and examine the information of the place to also want the feedback to packing. Pass the information share thus to make both the chain connect, becoming a total body, the match of your that thus make is more close, at each other attain to reflect the result that mutually flick.The PLC correspondence has already come more more body now its value, at the PLC and correspondence between PLCs, can pass the communication of the information and the share of the datas to guarantee that of the equipments moderates mutually, the result that arrive already to repair with each other. Data conversion the adoption RS232 between PLC connect to come to the transmission data, but the RS232 pick up a people and can guarantee 10 meters only of deliver the distance, if in the distance of 1000 meters we can pass the RS485 to carry on the correspondence, the longer distance can pass the MODEL only to carry on deliver.The PLC data transmission is just to be called a form to it in a piece of and continuous address that the data of the inner part delivers the other party, we, the PLC of the other party passes to read data in the watch to carry on the operation. If the data that data in the watch is a to establish generally, that is just the general data transmission, for example today of oil price rise, I want to deliver the price of the oil price to lose the oil ally on board, that is the share of the data; But take data in the watch for an instruction procedure that controls the PLC, that had the difficulty very much, for example you have to control one pedestal robot to press the action work that you imagine, you will draw up for it the form that a procedure combine with the data sends out to pass by.The form that information transport contain single work, the half a work and the difference of a workses .The meaning of the single work also is to say both, a can send out only, but a can receive only, for example a spy he can receive the designation of the superior only, but can't give the superior reply; A work of half is also 2 and can can send out similar to accept the data, but can't send out and accept at the same time, for example when you make a phone call is to can't answer the phone, the other party also; But whole pair works is both can send out and accept the data, and can send out and accept at the same time. Be like the Internet is a typical example.The process that information transport also has synchronous and different step cent: The data line and the clock lines are synchronous when synchronous meaning lie in sending out the data, is also the data signal and the clock signals to be carry on by the CPU to send out at the same time, this needs to all want the specialized clock signal each other to carry on the transmission and connect to send, and is constrained, the characteristics of this kind of method lies in its speed very quick, but correspond work time of take up the CPU and also want to be long oppositely, at the same time the technique difficulty also very big. Its request lies in can'ting have an error margins in a datas deliver, otherwise the whole piece according to compare the occurrence mistake, this on the hardware is a bigger difficulty. Applied more and more extensive in some appropriative equipmentses, be like the appropriative medical treatment equipments, the numerical signal equipments...etc., in compare the one data deliver,its result is very good.And the different step is an application the most extensive, this receive benefit in it of technique difficulty is opposite and want to be small, at the same time not need to prepare the specialized clock signal, its characteristics to lie in, its data is partition, the long-lost send out and accept, be the CPU is too busy of time can grind to a stop sex to work, also reduced the difficulty on the hardware, the data throw to lose at the same time opposite want to be little, we can pass the examination of the data to observe whether the data that we send out has the mistake or not, be like strange accidentally the method, tired addition and eight efficacies method etc., can use to helps whether the data that we examine to send out have or not the mistake occurrence, pass the feedback to carry on the discriminator.A line of transmission of the information contain a string of and combine the cent of: The usual PLC is 8 machines, certainly also having 16 machines. We can be an at the time of sending out the data a send out to the other party, also can be 88 send out the data to the other party, an and 8 differentiationses are also the as that we say to send out the data and combine sends out the data. A speed is more and slowly, but as long as 2 or three lines can solve problem, and can use the telephone line to carry on the long range control. But combine the oscular transmission speed is very quick of, it is a string of oscular of 25600%, occupy the advantage in the short distance, the in view of the fact TTL electricity is even, being limited by the scope of one meter generally, it combine unwell used for the data transmission of the long pull, thus the cost is too expensive.Under a lot of circumstances we are total to like to adopt the string to combine the conversion chip to carry on deliver, under this kind of circumstance not need us to carry on to depositted the machine to establish too and complicatedly, but carry on the data exchanges through the data transmission instruction directly, but is not a very viable way in the correspondence, because the PLC of the other party must has been wait for your data exportation at the time of sending out the data, it can't do other works.When you are reading the book, you hear someone knock on door, you stop tostart up of affair, open the door and combine to continue with the one who knock on door a dialogue, the telephone of this time rang, you signal hint to connect a telephone, after connecting the telephone through, return overdo come together knock on door to have a conversation, after dialogue complete, you continue again to see your book, this kind of circumstance we are called the interruption to it, it has the authority, also having sex of have the initiative, the PLC had such function .Its characteristics lie in us and may meet the urgently abrupt affairs in the operation process of the equipments, we want to stop to start immediately up of work, the whereabouts manages the more important affair, this kind of circumstance is we usually meet of, PLC while carry out urgent mission, total will keep the current appearance first, for example the address of the procedure, CPU of tired add the machine data etc., be like to to stick down which the book that we see is when we open the door the page or simply make a mark, because we treat and would still need to continue immediately after book of see the behind. The CPU always does the affair that should do according to our will, but your mistake of give it an affair, it also would be same to do, this we must notice.The interruption is not only a, sometimes existing jointly with the hour several inside break, break off to have the preferred Class, they will carry out the interruption of the higher Class according to person's request. This kind of breaks off the medium interruption to also became to break off the set. The Class that certainly break off is relevant according to various resources of CPU with internal PLC, also following a heap of capacity size of also relevant fasten.The contents that break off has a lot of kinds, for example the exterior break off, correspondence in of send out and accept the interruption and settle and the clock that count break off, still have the WDT to reset the interruption etc., they enriched the CPU to respond to the category while handle various business. Speak thus perhaps you can't comprehend the internal structure and operation orders of the interruption completely also, we do a very small example to explain.Each equipments always will not forget a button, it also is at we meet the urgent circumstance use of, that is nasty to stop the button. When we meet the Human body trouble and surprised circumstances we as long as press it, the machine stops alloperations immediately, and wait for processing the over surprised empress recover the operation again.Nasty stop the internal I/ O of the internal CPU of the button conjunction PLC to connect up, be to press button an exterior to trigger signal for CPU, the CPU carries on to the I/ O to examine again, being to confirm to have the exterior to trigger the signal, CPU protection the spot breaks off procedure counts the machine turn the homologous exterior I/ O automatically in the procedure to go to also, be exterior interruption procedure processing complete, the procedure counts the machine to return the main procedure to continue to work.Have 1:00 can what to explain is we generally would nasty stop the button of exterior break off to rise to the tallest Class, thus guarantee the safety.When we are work a work piece, giving the PLC a signal, counting PLC inner part the machine add 1 to compute us for a day of workload, a count the machine and can solve problem in brief, certainly they also can keep the data under the condition of dropping the electricity, urging the data not to throw to lose, this is also what we hope earnestly.The PLC still has the function that the high class counts the machine, being us while accept some datas of high speed, the high speed that here say is the data of the in all aspects tiny second class, for example the bar code scanner is scanning the data continuously, calculating high-speed signal of the data processor DSP etc., we will adopt the high class to count the machine to help we carry on count. It at the PLC carries out the procedure once discover that the high class counts the machine to should of interruption, will let go of the work on the hand immediately. The trapezoid diagram procedure that passes by to weave the distance again explains the high class for us to carry out procedure to count machine would automatic performance to should of work, thus rise the Class that the high class counts the machine to high one Class.You heard too many this phrases perhaps:" crash", the meaning that is mostly is a workload of CPU to lead greatly, the internal resources shortage etc. the circumstance can't result in procedure circulate. The PLC also has the similar circumstance, there is a watchdog WDT in the inner part of PLC, we can establishtime that a procedure of WDT circulate, being to appear the procedure to jump to turn the mistake in the procedure movement process or the procedure is busy, movement time of the procedure exceeds WDT constitution time, the CPU turn but the WDT reset the appearance. The procedure restarts the movement, but will not carry on the breakage to the interruption.The PLC development has already entered for network ages of correspondence from the mode of the one, and together other works control the net plank and I/ O card planks to carry on the share easily. A state software can pass all se hardwares link, more animation picture of keep the view to carries on the control, and cans pass the Internet to carry on the control in the foreign land, the blast-off that is like the absolute being boat No.5 is to adopt this kind of way to make airship go up the sky.The development of the higher layer needs our continuous effort to obtain.The PLC emergence has already affected a few persons fully, we also obtained more knowledge and precepts from the top one experience of the generation, coming to the continuous development PLC technique, push it toward higher wave tide.摘自《可编程控制器技术讨论与未来发展》中文翻译可编程控制器技术讨论与未来发展随着时代的发展,当今的技术也日趋完善、竞争愈演愈烈;单靠人工的操作已不能满足于目前的制造业前景,也无法保证更高质量的要求和高新技术企业的形象.人们在生产实践中看到,自动化给人们带来了极大的便利和产品质量上的保证,同时也减轻了人员的劳动强度,减少了人员上的编制.在许多复杂的生产过程中难以实现的目标控制、整体优化、最佳决策等,熟练的操作工、技术人员或专家、管理者却能够容易判断和操作,可以获得满意的效果.人工智能的研究目标正是利用计算机来实现、模拟这些智能行为,通过人脑与计算机协调工作,以人机结合的模式,为解决十分复杂的问题寻找最佳的途径我们在各种场合看到了继电器连接的控制，那已经是时代的过去，如今的继电器只能作为低端的基层控制模块或者简单的设备中使用到；而PLC的出现也成为了划时代的主题，通过极其稳定的硬件穿插灵活的软件控制，使得自动化走向了新的高潮。
PLC中英文资料外文翻译
可编程控制器技术讨论与未来发展学生姓名： ******所在院系： ******所学专业： ******导师姓名： ******完成时间：******外文资料PLCtechnique discussion and future developmentWith the development of the times, today's technology is maturing, competition intensified。
rely on manual operation does not satisfy the current industry outlook, there is no guarantee of higher quality requirements and high-tech corporate image.People saw in the production practice, automation to bring great convenience and product quality assurance, but also reduce the labor intensity, reducing the staff on the establishment in many complex production process is difficult to achieve target control, the overall optimization, optimal decision-making, skilled operatives, technicians or specialists, managers can easily determine and operate it, you can get satisfactory results. artificial intelligence research is the use of computers to achieve the target, the analog These intelligent behavior, through coordination of the human brain and a computer to combine human models for solving very complex problem of finding the best way.PLC's most important feature is: electrical engineer electrical hardware no longer spend too much scheming, as long as the button switch or sensor input connected to the PLC input point will solve the problem by connecting the output point contacts or relay to control the power of the boot device, and small power output devices can be connected directly.Contained within the PLC having a central processor of the CPU, and with an external I / O port expansion I / O interface and the memory addresses of three major components, CPU core is formed by one or more accumulators, which have the logical math capabilities, and can read the contents of the program memory to drive through the calculation of the corresponding memory and I / O interface。
外文翻译---微处理器报告
附录A 科技文章摘译MICROPROCESSOR REPORTAtmel A VR Brings RISC to 8-Bit WorldBetter Performance Than Other 8-Bit Chips With Same Low CostBy Jim TurleyProving the adage that all technologies eventually filter down into commodity products, Atmel has brought RISC design philosophy to 8-bit micro-controllers. Dubbed A VR, this new architecture provides all the usual benefits of RISC: faster clock rates, better performance, and more efficient compiler optimization. Atmel also promises better code density and lower cost than comparable 8-bit micro-controllers.A VR competes with several well-established micro-controller dynasties such as the 6805, 68HC11, and petition also comes from Microchip’s PIC family, a more modern design that’s expanded rapidly in the pas t few years. Atmel hopes A VR will appeal to embedded designers who are willing to tackle a new architecture to get more performance than the entrenched micro-controller families can provide.A VR is the first in-house CPU design from Atmel, a billion-dollar company better known for its flash memory and E2PROM products. The company also sells a dozen flash-based derivatives of the popular 8051family, which it produces under license from Intel.Design Melds RISC and Micro-controller IdeasThe CPU resembles most RISC processors but has smaller registers. It was originally developed by a pair of researchers in Trondheim,Norway, before their consultancy was acquired by Atmel in 1995. Core CPU development still takes place in Norway, while memory and peripheral dev elopment is centered in Atmel’s San Jose (Calif.) facility.The core features 32 identical 8-bit registers, as Figure 1 shows. Any register can hold addresses or data. Since 8-bit address pointers are fairly worthless even in an 8-bit device, the last six registers can be used in pairs, as address pointers. Dubbed X, Y, and Z, these three meta-registers can be used for any load or store operation. The pointers can be post incremented or predecremented at the programmer’s option.Finally, a 6-bit displacement can be added to the contents of the pointer, a useful option for addressing array elements. This mode is not available for the X pointer; that op code is reserved for the LDI (load immediate constant) instruction.Figure 1. Unlike other 8-bit controllers, A VR has a set of 32 8-bit registers. The last six registers can be paired to form three address pointers.As with many low-end micro-controllers, the register file is mapped into the address space, and vice versa. The first 32 bytes of memory, 0x00–0x1F, correspond to registers R0–R31. The chip’s status register—which contains the overflow, carry, sign, and other flags—as well as other ―internal‖ registers are also memory mapped. This allows any register to be manipulated using standard memory references instead of special control-register instructions.For all intents and purposes, the CPU has no pipeline. It retrieves both source operands, executes the instruction, and stores the result in a single clock cycle. Branch latency is one clock for taken branches. All operations are register-to-register; the chip follows a strict load/store model.The great majority of A VR instructions are 16 bits long. Only four 32-bit instructions exist, allowing limited use of absolute 16-bit addressing. A VR separates the program and data spaces; although data pointers can be 16 bits, the PC (program counter) is only 12 bits wide, for 8K of code space.Instruction Set As Regular As PossibleThe compact instruction set necessarily forces some compromises, the first of which affects immediate values (literals). Very few instructions accept immediate values, and those that do (ADIW, SUBI, ORI, etc.) work only on the upper half(R16–R31) of the register set, as Table 1 shows. Even after shaving a bit from the operand-specified field, these instructions sometimes have room for only 6-bit immediate values.Table 1. Atmel’s A VR 8-bit RISC instruction set follows a strict load/store model, with a few simple indirect addressing modes, including post increment and preferment. The architecture also includes a number of individual bit-manipulation instructions.The ADIW and SBIW instructions (add/subtract immediate from word) are even more restrictive, operating on only the last eight registers, R24–R31. These instructions are meant primarily to add small offsets (0–63 bytes) to the X, Y, and Z pointers.There is a wealth of conditional branch instructions: namely, two for each of the eight flags in the status register. With little 7-bit offsets, these instructions can deflect execution only 64 instructions in either direction. For bigger displacements, RJMP can shift code by 2K, which is usually plenty, given the chip’s small code space.A VR also has a collection of interesting ―skip‖ operations (SBRC, SBRS, SBIC, and SBIS) that skip over the next instruction if any bit in any register is set or clear. If the skipped instruction is a long-displacement jump, these skips can be usedto effectively create conditional long-displacement branches. Alternatively, they can be used to skip a single arithmetic or logical operation in a string of operations, creating conditional operations somewhat similar to ARM’s.None of the A VR chips has a native multiply operation—much less a divide—although one has been defined. As defined, MUL multiplies any two 8-bit registers and deposits the 16-bit result in R0 and R1.When implemented, MUL executes in just two clock cycles, which is five times fast er than the 68HC11’s 10 clocks; even Motorola’s newer 68HC12 (see MPR 5/27/96, p. 1) needs 3 clocks. Atmel expects to deploy its multiplier in future A VR chips as clock speeds increase and the chips take on simple signal-processing tasks.Instructions Are Rich in Bit ManipulationAs with most micro-controllers, the A VR family has a host of bit-twiddling options, including 16 explicit instructions to set and clear every flag in its status register. This seems like a lopsided use of op code space; the same result could have been achieved with normal logical operations. For deeply embedded applications, however, this was probably the right choice. Masking operations use precious address pointers and one or more registers; the SEx/CLx instructions use neither.The chip can also set or clear any bit in any general purpose or I/O register; SER and CLR wipe the contents of an entire register at once. SBR and CBR, which set or clear multiple bits at a time, are aliases for ORI and ANDI, respectively.Initial Launch Includes Five PartsAtmel launched its A VR product line with four basic chips: the 90S1200,the ’2313, the ’4414, and the ’8515. The latter three devices are very similar, differing mainly in the amount of memory on the chip: 2K, 4K, or 8K of flash, with the amount of on-chip SRAM and E2PROM also increasing.The runt of the litter, the 1200, has only 1K of flash memory, no SRAM,no peripherals, and a restricted instruction set. With neither SRAM nor an external bus, the 1200 must use on-chip flash for data storage, which will slow execution considerably unless programmers can get by with juggling the register set alone. The 1200 are also the only chip in the family currently in production. In 1,000-unit quantities, the 20-pin 90S1200 sells for a paltry $1.65.It’s not often that the number of data bits outnumbers the pins on the package, but Atmel managed to get close with its 1220 device, an 8-pin version of the 1200. After power, ground, and crystal connections, only four pins are free for I/O. Most A VR chips come in 20-pin DIP or SOIC packages, which provide access to more I/O lines; only in a 40-pin package do the chips bond out their address and data buses for access to external memory.All the parts are fabricated on Atmel’s four 0.8-micron two-layer-metal fab lines in Colorado Springs and Rousset (France). This is the same memory process Atmel uses for its E2PROM and flash devices, and for its 8051 chips with integrated flash. The 1200 measure about 24mm2 overall, and as the die photo in Figure 2 shows, the chip is nearly all logic. Memory processes typically don’t produce very compact (or fast) logic, but most A VR chips will be dominated by memory and peripherals, and clock speeds aren’t very high.Figure 2. The 90S1200 m easures about 4.3 ´ 5.5 mm in Atmel’s 0.8-micron two-layer-metal flash-memory process.For Once, RISC Techniques Improve Code DensityIt’s sometimes hard to get excited about 8-bit processors, yet Atmel’s A VR design is as different from others in its class as the first RISC machine was from big systems more than a decade ago. With its large register file and orthogonal instruction set, A VR is far more modern than its competitors.Atmel’s new CPU will be particularly appealing to programmers moving down the microprocessor food chain from 32-bit or 16-bit chips and who are accustomed to flexible register sets. For programmers moving up from, say, the 8051, A VR will be a real eye-opener.For example, the 8051, 6805, and PIC all make do with a single accumulator; the68HC11 and ’HC12 have just two. This makes A VR easier to program at the assembly level and easier to optimize with a compiler. The big register set reduces dependence on memory, which improves speed and shrinks data-storage requirements.Counterintuitively, A VR’s RISC-like instruction set also helps improve its code density over that of other 8-bitters, according to Atmel. Its CPI (compare immediate) instruction avoids the relatively awkward construct of loading, subtracting, and checking flags used on the 6805 and PIC. Adding two numbers on the 8051, 6805, or PIC usually involves shuffling both operands through the accumulator and storing the result; A VR simply adds two registers with one instruction in one cycle.A VR is not pure RISC-some instructions are longer than others—nor is it the first 8-bit micro-controller with a big register file. Zilog’s ever-popular Z8 has 16 banks of 16 registers and a very orthogonal instruction set. But at 5–15 clocks per instruction, the Z8 c an’t match A VR’s speed.Atmel Takes On Million SellersThe 6805, 8051, and 68HC11 are the top-selling 8-bit families in the world, shipping millions of units every month. Motorola, for example, shipped itstwo-billionth 68HC05 in April. While A VR will not instantly overthrow these titans, it does provide substantial advantages over the entrenched leaders and blurs the line between 8- and 16-bit performances.Although ―high-performance‖ seems misplaced here, the A VR family should outperform other 8-bit micro-controllers and many 16-bit chips. At 20 MHz,its top clock rate is easily double that of other chips in its class. More important, almost all instructions execute in 1 or 2 clock cycles, versus 5–10 cycles for 8051, 6805, 68HC11, and PIC chips.There is no lack of alternatives for the 8-bit user looking for more speed. Motorola’s 68HC12 is a step up from the ’HC11; Philips and Intel are enticing 8051 users with the 8051XA (see MPR 10/3/94, p. 17) or the 251 family. Of these, Intel offers the smoothest upgrade path, with complete binary compatibility between the 8051 and the 251. Philips and Motorola both tout substantial size and speed advantages for users willing to reassemble (or recompile) their code.The ’HC12, 8051XA, and 251 are more accurately 16- bit designs, with 16-bit internal data paths and 16-bit arithmetic operations, but they still require three or more clocks for even the simplest calculations and most basic register operations. Moreover, the clock rates of these parts are not substantially faster than Atmel’s and can’t make up for inherently inefficient execution.In short, A VR offers 16-bit performance at an 8-bit price. For users who want on-chip memory but don’t need 16-bit data types or binary compatibility with aprevious generation, Atmel offers better price/performance for designers willing to let go of the older families’ apron strings.微处理器报告吉姆﹒泰罗随着所有技术渗入到日用品中，Atmel已经把精简指令集计算机设计原理变成8位微控制器。
可编程控制器外文翻译、中英文翻译、外文文献翻译
毕业设计中英文翻译院系专业班级姓名学号指导教师20**年 4 月Programmable Logic Controllers (PLC)1、MotivationProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicating [Moody and Morley, 1999, p. 110]:`If houses were built like software projects, a single woodpecker could destroy civilization.”Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladder logic programs. Though the hardware costs of PLCs are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLCs can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC basedsoftware design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than SO0/a of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs [Rockwell, 1999].In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.PLCs (programmable logic controllers) are the control hubs for a wide variety of automated systems and processes. They contain multiple inputs and outputs that use transistors and other circuitry to simulate switches and relays to control equipment. They are programmable via software interfaced via standard computer interfaces and proprietary languages and network options.Programmable logic controllers I/O channel specifications include total number of points, number of inputs and outputs, ability to expand, and maximum number of channels. Number of points is the sum of the inputs and the outputs. PLCs may be specified by any possible combination of these values. Expandable units may be stacked or linked together to increase total control capacity. Maximum number of channels refers to the maximum total number of input and output channels in an expanded system. PLC system specifications to consider include scan time, number of instructions, data memory, and program memory. Scan time is the time required by the PLC to check the states of its inputs and outputs. Instructions are standard operations (such as math functions) available to PLC software. Data memory is the capacity for data storage. Program memory is the capacity for control software.Available inputs for programmable logic controllers include DC, AC, analog, thermocouple, RTD, frequency or pulse, transistor, and interrupt inputs. Outputs for PLCs include DC, AC, relay, analog, frequency or pulse, transistor, and triac. Programming options for PLCs include front panel, hand held, and computer.Programmable logic controllers use a variety of software programming languages for control. These include IEC 61131-3, sequential function chart (SFC), function block diagram (FBD), ladder diagram (LD), structured text (ST), instruction list (IL), relay ladder logic (RLL), flow chart, C, and Basic. The IEC 61131-3 programming environment provides support for five languages specified by the global standard: Sequential Function Chart,Function Block Diagram, Ladder Diagram, Structured Text, and Instruction List. This allows for multi-vendor compatibility and multi-language programming. SFC is a graphical language that provides coordination of program sequences, supporting alternative sequence selections and parallel sequences. FBD uses a broad function library to build complex procedures in a graphical format. Standard math and logic functions may be coordinated with customizable communication and interface functions. LD is a graphic language for discrete control and interlocking logic. It is completely compatible with FBD for discrete function control. ST is a text language used for complex mathematical procedures and calculations less well suited to graphical languages. IL is a low-level language similar to assembly code. It is used in relatively simple logic instructions. Relay Ladder Logic (RLL), or ladder diagrams, is the primary programming language for programmable logic controllers (PLCs). Ladder logic programming is a graphical representation of the program designed to look like relay logic. Flow Chart is a graphical language that describes sequential operations in a controller sequence or application. It is used to build modular, reusable function libraries. C is a high level programming language suited to handle the most complex computation, sequential, and data logging tasks. It is typically developed and debugged on a PC. BASIC is a high level language used to handle mathematical, sequential, data capturing and interface functions.Programmable logic controllers can also be specified with a number of computer interface options, network specifications and features. PLC power options, mounting options and environmental operating conditions are all also important to consider.2、ResumeA PLC (programmable Logic Controller) is a device that was invented to replace the necessary sequential relay circuits for control.The PLC works by looking at its input and depending upon their state, turning on/off its outputs. The user enters a program, usually via software or programmer, which gives the desired results.PLC is used in many "real world" applications. If there is industry present, chance are good that there is a PLC present. If you are involved in machining, packing, material handling, automated assembly or countless other industries, you are probably already using them. If you are not, you are wasting money and time. Almost any application that needs some type of electrical control has a need for a PLC.For example, let's assume that when a switch turns on we want to turn a solenoid on for 5second and then turn it off regardless of how long the switch is on for. We can do this with a simple external timer. But what if the process included 10 switches and solenoids? We should need 10 external times. What if the process also needed to count how many times the switch individually turned on? We need a lot of external counters.As you can see the bigger the process the more of a need we have for a PLC. We can simply program the PLC to count its input and turn the solenoids on for the specified time.We will take a look at what is considered to be the "top 20" PLC instructions. It can be safely estimated that with a firm understanding of these instructions one can solve more than 80% of the applications in existence.Of course we will learn more than just these instruction to help you solve almost ALL potential PLC applications.The PLC mainly consists of a CPU, memory areas, and appropriate circuits to receive input/output data. We can actually consider the PLC to be a box full of hundreds or thousands of separate relay, counters, times and data storage locations,Do these counters,timers, etc. really exist? No,they don't "physically" exist but rather they simulated and be considered software counters, timers, etc. . These internal relays are simulated through bit locations in registers.What does each part do? Let me tell you.Input RelaysThese are connected to the outside world.They physically exsit and receive signals from switches,sensors,ect..Typically they are not relays but rather they are transistors.Internal Utility RelaysThese do not receive signals from the outside world nor do they physically exist.they are simulated relays and are what enables a PLC to eliminate external relays.There are also some special relays that are dedicated to performing only one task.Some are always on while some are always off.Some are on only once during power-on and are typically used for initializing data that was stored.CountersThese again do not physically exist. They are simulated counters and they can be programmed to count pulses.Typically these counters can count up,down or both up anddown.Since they are simulated,they are limited in their counting speed.Some manufacturers also include high-speed counters that are hardware based.We think of these as physically existing.Most times these counters can count up,down or up and down.TimersThese also do not physically exist.They come in many varieties and increments.The most common type is an on-delay type.Others include off-delays and both retentive and non-retentive types.Increments vary from 1ms through 1s.Output RelaysThere are connected to the outside world.They physically exist and send on/off signals to solenoids,lights,etc..They can be transistors,relays,or triacs depending upon the model chosen Data StorageTypically there are registers assigned to simply store data.They are usually used as temporary storage for math or data manipulation.They can also typically be used to store data when power is removed form the PLC.Upon power-up they will still have the same contents as before power was moved.Very convenient and necessary!A PLC works by continually scanning a program.We can think of this scan cycle as consisting of 3 important steps.There are typically more than 3 but we can focus on the important parts and not worry about the others,Typically the others are checking the system and updating the current internal counter and timer values,Step 1 is to check input status,First the PLC takes a look at each input to determine if it is on off.In other words,is the sensor connected to the first input on?How about the third...It records this data into its memory to be used during the next step.Step 2 is to execute program.Next the PLC executes your program one instruction at a time.Maybe your program said that if the first input was on then it should turn on the first output.Since it already knows which inputs are on/off from the previous step,it will be able to decide whether the first output should be turned on based on the state of the first input.It will store the execution results for use later during the next step.Step 3 is to update output status.Finally the PLC updates the status the outputs.It updates the outputs based on which inputs were on during the first step and the results executing your program during the second step.Based on the example in step 2 it would now turn on the firstoutput because the first input was on and your program said to turn on the first output when this condition is true.After the third step the PLC goes back to step one repeats the steps continuously.One scan time is defined as the time it takes to execute the 3 steps continuously.One scan time is defined as the time it takes to execute the 3 steps listed above.Thus a practical system is controlled to perform specified operations as desired.3、PLC StatusThe lack of keyboard, and other input-output devices is very noticeable on a PLC. On the front of the PLC there are normally limited status lights. Common lights indicate;power on - this will be on whenever the PLC has powerprogram running - this will often indicate if a program is running, or if no program is runningfault - this will indicate when the PLC has experienced a major hardware or software problemThese lights are normally used for debugging. Limited buttons will also be provided for PLC hardware. The most common will be a run/program switch that will be switched to program when maintenance is being conducted, and back to run when in production. This switch normally requires a key to keep unauthorized personnel from altering the PLC program or stopping execution. A PLC will almost never have an on-off switch or reset button on the front. This needs to be designed into the remainder of the system.The status of the PLC can be detected by ladder logic also. It is common for programs to check to see if they are being executed for the first time, as shown in Figure 1. The ’first scan’ input will be true on the very first time the ladder logic is scanned, but false on every other scan. In this case the address for ’first scan’ in a PLC-5 is ’S2:1/14’. With the logic in the example the first scan will seal on ’light’, until ’clear’ is turned on. So the light will turn on after the PLC has been turned on, but it will turn off and stay off after ’clear’ is turned on. The ’first scan’ bit is also referred to at the ’first pass’ bit.Figure 1 An program that checks for the first scan of the PLC4、Memory TypesThere are a few basic types of computer memory that are in use today.RAM (Random Access Memory) - this memory is fast, but it will lose its contents when power is lost, this is known as volatile memory. Every PLC uses this memory for the central CPU when running the PLC.ROM (Read Only Memory) - this memory is permanent and cannot be erased. It is often used for storing the operating system for the PLC.EPROM (Erasable Programmable Read Only Memory) - this is memory that can be programmed to behave like ROM, but it can be erased with ultraviolet light and reprogrammed.EEPROM (Electronically Erasable Programmable Read Only Memory) – This memory can store programs like ROM. It can be programmed and erased using a voltage, so it is becoming more popular than EPROMs.All PLCs use RAM for the CPU and ROM to store the basic operating system for the PLC. When the power is on the contents of the RAM will be kept, but the issue is what happens when power to the memory is lost. Originally PLC vendors used RAM with a battery so that the memory contents would not be lost if the power was lost. This method is still in use, but is losing favor. EPROMs have also been a popular choice for programming PLCs. The EPROM is programmed out of the PLC, and then placed in the PLC. When the PLC is turned on the ladder logic program on the EPROM is loaded into the PLC and run. This method can be very reliable, but the erasing and programming technique can be time consuming. EEPROM memories are a permanent part of the PLC, and programs can be stored in them like EPROM. Memory costs continue to drop, and newer types (such as flash memory) are becoming available, and these changes will continue to impact PLCs.5、Objective and Significance of the ThesisThe objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of theautomation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer.A systematic approach to designing PLC software can overcome deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a high-level description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, well-defined control systems design outcomes are conducive to automatic code generation- An ability to produce control software executable on commercial distinct logic controllers can reduce programming lead-time and labor cost. In particular, the thesis is relevant with respect to the following aspect Customer-Driven ManufacturingIn modern manufacturing, systems are characterized by product and process innovation, become customer-driven and thus have to respond quickly to changing system requirements.A major challenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused in real-time, therefore, giving a significant competitive edge in industrial practice.Higher Degree of Design Automation and Software QualityStudies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of computing resources. For instance, the programming of PLCs still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debugging may consume over 50% of the manpower allocated for the PLC program design. Standards [IEC 60848, 1999; IEC-61131-3, 1993; IEC 61499, 1998; ISO 15745-1, 1999] have been formed to fix and disseminate state-of-the-art design methods, but they normally cannot participate in advancingthe knowledge of efficient program and system design.A systematic approach will increase the level of design automation through reusing existing software components, and will provide methods to make large-scale system design manageable. Likewise, it will improve software quality and reliability and will be relevant to systems high security standards, especially those having hazardous impact on the environment such as airport control, and public railroads.System ComplexityThe software industry is regarded as a performance destructor and complexity generator. Steadily shrinking hardware prices spoils the need for software performance in terms of code optimization and efficiency. The result is that massive and less efficient software code on one hand outpaces the gains in hardware performance on the other hand. Secondly, software proliferates into complexity of unmanageable dimensions; software redesign and maintenance-essential in modern automation systems-becomes nearly impossible. Particularly, PLC programs have evolved from a couple lines of code 25 years ago to thousands of lines of code with a similar number of 1/O points. Increased safety, for instance new policies on fire protection, and the flexibility of modern automation systems add complexity to the program design process. Consequently, the life-cycle cost of software is a permanently growing fraction of the total cost. 80-90% of these costs are going into software maintenance, debugging, adaptation and expansion to meet changing needs [Simmons et al., 1998].Design Theory DevelopmentToday, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineering systems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering design.Application in Logical Hardware DesignFrom a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a component design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design.可编程控制器1、前言可编程序的逻辑控制器（PLC），是由Richard E.Morley 于1968年发明的，如今已经被广泛的应用于生产、运输、化学等工业中。
电气工程及其自动化专业 外文文献 英文文献 外文翻译 plc方面
1、外文原文（复印件）A: Fundamentals of Single-chip MicrocomputerTh e si ng le-ch i p mi cr oc om pu ter is t he c ul mi nat i on o f bo th t h e d ev el op me nt o f th e d ig it al com p ut er an d t he int e gr at ed ci rc ui ta r gu ab ly th e t ow m os t s i gn if ic ant i nv en ti on s o f t h e 20t h c en tu ry[1].Th es e to w typ e s of a rc hi te ctu r e ar e fo un d i n s in gl e-ch ip m i cr oc om pu te r. So m e em pl oy t he sp l it p ro gr am/d ata me mo ry o f th e H a rv ar d ar ch it ect u re, sh ow n i n -5A, ot he rs fo ll ow th e ph i lo so ph y, w i de ly a da pt ed fo r g en er al-p ur pos e c om pu te rs an d m i cr op ro ce ss or s, o f m a ki ng no lo gi c al di st in ct io n b e tw ee n p ro gr am a n d da t a m em ory a s i n th e Pr in cet o n ar ch it ec tu re,sh ow n in-5A.In g en er al te r ms a s in gl e-chi p m ic ro co mp ut er i sc h ar ac te ri zed b y the i nc or po ra tio n of al l t he uni t s o f a co mp ut er i n to a s in gl e dev i ce, as s ho wn in Fi g3-5A-3.-5A-1 A Harvard type-5A. A conventional Princeton computerFig3-5A-3. Principal features of a microcomputerRead only memory (ROM).R OM i s u su al ly f or th e p er ma ne nt, n o n-vo la ti le s tor a ge o f an a pp lic a ti on s pr og ra m .M an ym i cr oc om pu te rs an d mi cr oc on tr ol le r s a re in t en de d fo r h ig h-v ol ume a p pl ic at io ns a nd h en ce t he e co nom i ca l ma nu fa ct ure of t he d ev ic es r e qu ir es t ha t the co nt en ts o f the pr og ra m me mo ry b e co mm it te dp e rm an en tl y d ur in g th e m an uf ac tu re o f c hi ps . Cl ear l y, th is im pl ie sa ri g or ou s a pp roa c h t o R OM co de d e ve lo pm en t s in ce c ha ng es ca nn otb e m ad e af te r man u fa ct ur e .T hi s d e ve lo pm en t pr oce s s ma y in vo lv e e m ul at io n us in g a s op hi st ic at ed deve lo pm en t sy st em w i th a ha rd wa re e m ul at io n ca pa bil i ty a s we ll a s th e u se of po we rf ul so ft wa re t oo ls.So me m an uf act u re rs p ro vi de ad d it io na l RO M opt i on s byi n cl ud in g i n th ei r ra ng e de vi ce s wi th (or i nt en de d fo r us e wi th) u s er pr og ra mm ab le m em or y. Th e s im p le st of th es e i s us ua ll y d ev ice w h ic h ca n op er ate in a m ic ro pr oce s so r mo de b y usi n g so me o f th e i n pu t/ou tp ut li ne s as a n ad dr es s an d da ta b us f or acc e ss in g e xt er na l m e mo ry. T hi s t ype o f d ev ic e c an b e ha ve fu nc ti on al l y a s t he si ng le c h ip mi cr oc om pu te r fr om wh ic h i t i s de ri ve d a lb eit w it h r es tr ic ted I/O an d a mo di fie d e xt er na l ci rcu i t. T he u se o f t h es e RO Ml es sd e vi ce s is c om mo n e ve n in p ro du ct io n c ir cu it s wh er e t he v ol um e do es n o t ju st if y th e d e ve lo pm en t co sts of c us to m on-ch i p RO M[2];t he re c a n st il l b e a si g ni fi ca nt s a vi ng in I/O a nd ot he r c hi ps co mp ar ed t o a c on ve nt io nal mi cr op ro ce ss or b as ed c ir cu it. M o re e xa ctr e pl ac em en t fo r RO M d ev ic es c an b e o bt ai ne d in t he f o rm o f va ri an ts w i th 'pi gg y-ba ck'EP RO M(Er as ab le p ro gr am ma bl e ROM)s oc ke ts o rd e vi ce s w it h EP ROM i ns te ad o f R OM 。
(完整版)PLC英文文献+翻译
自动化专业本科毕业设计英文翻译学院(部)：专业班级：学生姓名：指导教师：年月日Programmable Logic ControllerONE：PLC overviewProgrammable controller is the first in the late 1960s in the United States, then called PLC programmable logic controller (Programmable Logic Controller) is used to replace relays. For the implementation of the logical judgment, timing, sequence number, and other control functions. The concept is presented PLC General Motors Corporation. PLC and the basic design is the computer functional improvements, flexible, generic and other advantages and relay control system simple and easy to operate, such as the advantages of cheap prices combined controller hardware is standard and overall. According to the practical application of target software in order to control the content of the user procedures memory controller, the controller and connecting the accused convenient target.In the mid-1970s, the PLC has been widely used as a central processing unit microprocessor, import export module and the external circuits are used, large-scale integrated circuits even when the Plc is no longer the only logical (IC) judgment functions also have data processing, PID conditioning and data communications functions. International Electro technical Commission (IEC) standards promulgated programmable controller for programmable controller draft made the following definition : programmable controller is a digital electronic computers operating system, specifically for applications in the industrial design environment. It used programmable memory, used to implement logic in their internal storage operations, sequence control, timing, counting and arithmetic operations, such as operating instructions, and through digital and analog input and output, the control of various types of machinery or production processes. Programmable controller and related peripherals, and industrial control systems easily linked to form a whole, to expand its functional design. Programmable controller for the user, is a non-contact equipment, the procedures can be changed to change production processes. The programmable controller has become a powerful tool for factory automation, widely popular replication.Programmable controller is user-oriented industries dedicated control computer, with many distinctive features.First, high reliability, anti-interference capability;Second，programming visual, simple;Third, adaptability good;Fourth functional improvements, strong functional interface. TWO：History of PLCProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLC per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicatingIf houses were built like software projects, a single woodpecker could d estroy civilization.”Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladderlogic programs. Though the hardware costs of PLC are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLC can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC based software design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs.In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.The objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of the automation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer. Three：now of PLCFrom the structure is divided into fixed PLC and Module PLC, the two kinds of PLC including CPU board, I/O board, display panel, memory block, power, these elements into a do not remove overall. Module type PLC including CPU module, I/O modules, memory, thepower modules, bottom or a frame, these modules can be according to certain rules combination configuration.In the user view, a detailed analysis of the CPU's internal unnecessary, but working mechanism of every part of the circuit. The CPU control works, by it reads CPU instruction, interprets the instruction and executes instructions. But the pace of work by shock signal control.Unit work under the controller command used in a digital or logic operations.In computing and storage register of computation result, it is also among the controller command and work. CPU speed and memory capacity is the important parameters fot PLC . its determines the PLC speed of work, IO PLC number and software capacity, so limits to control size.Central Processing Unit (CPU) is the brain of a PLC controller. CPU itself is usually one of the microcontrollers. Aforetime these were 8-bit microcontrollers such as 8051, and now these are 16-and 32-bit microcontrollers. Unspoken rule is that you’ll find mostly Hitachi and Fujicu microcontrollers in PLC controllers by Japanese makers, Siemens in European controllers, and Motorola microcontrollers in American ones. CPU also takes care of communication, interconnectedness among other parts of PLC controllers, program execution, memory operation, overseeing input and setting up of an output.System memory (today mostly implemented in FLASH technology) is used by a PLC for a process control system. Aside form. this operating system it also contains a user program translated foram ladder diagram to a binary form. FLASH memory contents can be changed only in case where user program is being changed. PLC controllers were used earlier instead of PLASH memory and have had EPROM memory instead of FLASH memory which had to be erased with UV lamp and programmed on programmers. With the use of FLASH technology this process was greatly shortened. Reprogramming a program memory is done through a serial cable in a program for application development.User memory is divided into blocks having special functions. Some parts of a memory are used for storing input and output status. The real status of an input is stored either as “1”or as “0”in a specific memory bit/each input or output has one corresponding bit in memory. Other parts of memory are used to store variable contents for variables used in used program. For example, time value, or counter value would be stored in this part of the memory.PLC controller can be reprogrammed through a computer (usual way), but also through manual programmers (consoles). This practically means that each PLC controller can programmed through a computer if you have the software needed for programming. Today’s transmission computers are ideal for reprogramming a PLC controller in factory itself. This is of great importance to industry. Once the system is corrected, it is also important to read the right program into a PLC again. It is also good to check from time to time whether program in a PLC has not changed. This helps to avoid hazardous situations in factory rooms (some automakers have established communication networks which regularly check programs in PLC controllers to ensure execution only of good programs).Almost every program for programming a PLC controller possesses various useful options such as: forced switching on and off of the system input/outputs (I/O lines), program follow up in real time as well as documenting a diagram. This documenting is necessary to understand and define failures and malfunctions. Programmer can add remarks, names of input or output devices, and comments that can be useful when finding errors, or with system maintenance. Adding comments and remarks enables any technician (and not just a person who developed the system) to understand a ladder diagram right away. Comments and remarks can even quote precisely part numbers if replacements would be needed. This would speed up a repair of any problems that come up due to bad parts. The old way was such that a person who developed a system had protection on the program, so nobody aside from this person could understand how it was done. Correctly documented ladder diagram allows any technician to understand thoroughly how system functions.Electrical supply is used in bringing electrical energy to central processing unit. Most PLC controllers work either at 24 VDC or 220V AC. On some PLC controllers you’ll find electrical supply as a separatemodule. Those are usually bigger PLC controllers, while small and medium series already contain the supply module. User has to determine how much current to take from I/O module to ensure that electrical supply provides appropriate amount of current. Different types of modules use different amounts of electrical current.This electrical supply is usually not used to start external input or output. User has to provide separate supplies in starting PLC controller inputs because then you can ensure so called “pure” supply for the PLC controller. With pure supply we mean supply where industrial environment can not affect it damagingly. Some of the smaller PLC controllers supply their inputs with voltage from a small supply source already incorporated into a PLC.Four：PLC design criteriaA systematic approach to designing PLC software can overcome deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a high-level description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, well-defined control systems design outcomes are conducive to automatic code generation- An ability to produce control software executable on commercial distinct logic controllers can reduce programming lead-time and labor cost. In particular, the thesis is relevant with respect to the following aspects.In modern manufacturing, systems are characterized by product and process innovation, become customer-driven and thus have to respond quickly to changing system requirements. A major challenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused inreal-time, therefore, giving a significant competitive edge in industrial practice.Studies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of computing resources. For instance, the programming of PLC still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debugging may consume over 50% of the manpower allocated for the PLC program design. Standards [IEC 60848, 1999; IEC-61131-3, 1993; IEC 61499, 1998; ISO 15745-1, 1999] have been formed to fix and disseminate state-of-the-art design methods, but they normally cannot participate in advancing the knowledge of efficient program and system design.A systematic approach will increase the level of design automation through reusing existing software components, and will provide methods to make large-scale system design manageable. Likewise, it will improve software quality and reliability and will be relevant to systems high security standards, especially those having hazardous impact on the environment such as airport control, and public railroads.The software industry is regarded as a performance destructor and complexity generator. Steadily shrinking hardware prices spoils the need for software performance in terms of code optimization and efficiency. The result is that massive and less efficient software code on one hand outpaces the gains in hardware performance on the other hand. Secondly, software proliferates into complexity of unmanageable dimensions; software redesign and maintenance-essential in modern automation systems-becomes nearly impossible. Particularly, PLC programs have evolved from a couple lines of code 25 years ago to thousands of lines of code with a similar number of 1/O points. Increased safety, for instance new policies on fire protection, and the flexibility of modern automation systems add complexity to the program design process. Consequently, the life-cycle cost of software is a permanently growing fraction of the total cost. 80-90% of these costs are going into software maintenance, debugging, adaptation and expansion to meet changing needs.Today, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineering systems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering design.From a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a component design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design.可编程控制器一、PLC概述可编程控制器是60年代末在美国首先出现的，当时叫可编程逻辑控制器PLC（Programmable Logic Controller），目的是用来取代继电器。
自动化专业-外文文献-英文文献-外文翻译-plc方面
1、外文原文（复印件)A: Fundamentals of Single-chip MicrocomputerTh e si ng le-ch i p mi cr oc om pu ter is t he c ul mi nat i on o f bo th t h e d ev el op me nt o f th e d ig it al com p ut er an d t he int e gr at ed ci rc ui ta r gu ab ly th e t ow m os t s i gn if ic ant i nv en ti on s o f t h e 20t h c en tu ry[1].Th es e to w t ype s o f a rc hi te ct ur e a re fo un d i n s i ng le—ch ip m i cr oc om pu te r。
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ARM微处理器外文翻译
1 The introduction and development of microprocessor1.1 The history of the MicroprocessorThe first microprocessor was originally developed for a calculator, and revolutionary for its time, it contained 2,300 transistors on a 4-bit microprocessor that could perform only 60,000 operations per second. The first 8-bit microprocessor was the Intel 8008, developed in 1972 to run computer terminals. The Intel 8008 contained 3,300 transistors. The first truly general-purpose microprocessor, developed in 1974, was the 8-bit Intel 8080 (see Microprocessor, 8080), which contained 4,500 transistors and could execute 200,000 instructions per second. Modern Microprocessors have much greater capacity and speed. They include the Intel Pentium Pro, containing 5.5 million transistors.1.2 The future Technology of the MicroprocessorThe technology of microprocessors and integrated-circuit is developing rapidly. Currently, the most sophisticated microprocessors contain about ten million transistors. By the year 2000, advanced microprocessors are expected to contain more than 50 million transistors, and about 800 million by 2010.Lithographic techniques will also require improvements. By the year 2000, minimum element size is less than 0.2 micros. At these dimensions, even short-wave-length ultraviolet light may not reach the necessary resolution. Alternative possibilities include using very narrow beams of electrons and ions or replacing optical lithography with lithography that uses X rays of extremely short wavelength. Using these technologies, clock speeds could increase to more than 1,000 MHz by 2010. It is expected that the limiting factor in microprocessor performance will be the behavior of the electrons themselves as they are propelled through the transistors. At extremely small dimensions, quantum effects due to the wavelike nature of electrons could dominate the behavior of transistors and circuits. New devices and circuit designs may be necessary as microprocessors approach atomic dimensions. Techniques including molecular-beam epitaxy, in which semiconductors are layered one atom at a time in an ultra-high-vacuum chamber, and scanning tunneling microscopy, whereby single atoms can be viewed and even moved with atomic precision, may be the tools needed to produce future generations of microprocessors.1.3 The introduction of the MicroprocessorThe microprocessor is one type of ultra-large-scale integrated circuit. Integrated circuits, also known as microchips or chips, are complex electronic circuits consisting of extremely tiny components formed on a single, thin, flat piece of material known as a semiconductor. Modern microprocessors incorporate as many as ten million transistors (which act as electronic amplifiers, oscillators, or, most commonly, switches), in addition to other components such as resistors, diodes, capacitors, and wires, all packed into an area about the size of a postage stamp.A microprocessor consists of several different sections: the arithmetic/logic unit （ALU）performs calculations on numbers and makes logical decisions; the registers are special memory locations for storing temporary information much as a scratch pad does; the control unit deciphers programs; bused carry digital information throughout the chip and computer; and local memory supports on-chip computation. More complex microprocessors often contain other sections-such as sections of specialized memory, called cache memory ,to spend up access external data-storage devices. Modern microprocessors operate with bus widths of 64 bits （binary digits, or units of information represented as 1s and 0s）,meaning that 64 bits of data can be transferred at the same time.A crystal oscillator in the computer provides a clock signal to coordinate all activities of the microprocessor. The clock speed of the most advanced microprocessors is about 300 megahertz (MHz) —about 300 million cycles per second—allowing about a billion computer instructions to be executed every second.Microprocessor’s functions is the central process ing unit of a computer, providing computational control. Microprocessors are also used in other advanced electronic systems, such as computer printers, automobiles, and jetairlines.1.4 MicrocontrollerA microprocessor is not a complete computer. It does not contain large amounts of memory or have the ability to communicate with input devices-such as keyboards, joy-sticks, and mice-or with output devices, such as monitors and printers. A different kind of integrated circuit, a microcontroller, is a complete computer on a chip, containing all of the elements of the basic microprocessor along with other specialized functions. Microcontrollers are used in video games, videocassette recorders (VCRs), automobiles, and other machines.1.5 Construction of MicroprocessorThe first step in producing a microprocessor is the creation of an ultrapure silicon substrate, a silicon slice in the shape of a round wafer that is polished to a mirror like smoothness. At present, the largest wafers used in industry are 200 mm (8 in) in diameter.In the oxidation step, an electrically nonconducting layer, called a dielectric, is placed between each conductive layer on the wafer. The most important type of dielectric is silicon, which is ‘grown’ by exposing the silicon wafer to oxyg en in a furnace at about 1000℃(about 1800℉). The oxygen combines with the silicon to form a thin layer of oxide about 75 angstroms deep (an angstrom is one ten-billionth of a meter).Microprocessor are fabricated using techniques similar to those used for other integrated circuits, such as memory chips. Microprocessors generally have a more complex structure than do other chips, and their manufacture requires extremely precise techniques. Economical manufacturing of microprocessors requires mass production. Several hundred dies, or circuit patterns, are created on the surface of a silicon wafer simultaneously. Microprocessor s are constructed by a process of deposition and removal of conducting, insulating, and semiconducting materials, one thin layer at a time until, after hundreds of separate steps, a complex sandwich is constructed that contains all the interconnected circuitry of the microprocessor. Only the outer surface of the silicon wafer-a layer about 10 microns (about 0.01 mm/0.0004 in) thick (about one-tenth the thickness of a human hair)—is used for the electronic circuit. The processing steps include substrate creation, oxidation, lithography, etching, ion implantation, and film deposition.Nearly every layer that is deposited on the wafer must be patterned accurately into the shape of the transistors and other electronic elements. Usually this is done in process known as photolithography, which is analogous to transforming the wafer into a piece of photographic film and projecting a picture of the circuit on it. A coating on the surface of the wafer, called the photoresist or resist, changes when exposed to light, making it easy to dissolve in a developing solution. These patterns are as small as 0.25 microns in size. Because the shortest wavelength of visible light is about 0.5 microns, Short-wave-length ultraviolet light must be used to resolve the tiny details of the patterns. After photolithography, the wafer is etched-that is, the resist is removed from the wafer either by chemicals, in a special vacuum chamber.In the next step of the process, ion implantation, impurities such as boron and phosphorus are introduced into the silicon to alter its conductivity. This is accomplished by ionizing the boron or phosphorus atoms (stripping off one or two electrons) and propelling them at the wafer with an iron implanter at very high energies. The ions become embedded in the surface of the wafer.Microprocessor features are so small and precise that a single speck of dust can destroy an entire die. The rooms used for microprocessor creation are called clean rooms because the air in them is extremely well filtered and virtually free of dust. The purest of today’s clean rooms are referred to as class 1, indicating the maximum number of allowed particles larger than 0.12 micron in one cubic foot of air. （For comparison, a typical home is class one million or so.）The thin layers used to build up a microprocessor are referred to as films. In the final step of the process, the films are deposited using sputterers in which thin films are grown in a plasma; by means of evaporation, whereby the material is melted and then evaporated coating the wafer; or by means of chemical-vapor deposition, whereby the material condenses from a gas at low or atmospheric pressure. In each case, the film must be of high purity and its thickness must be controlled within a small fraction of a micron.2 ARM－Advanced RISC MachinesARM- Advanced RISC Machinesis thought to be a company name, can be considered to be a type known as the microprocessor, can be considered a technical name.ARM company was established in Cambridge in 1991, It mainly sales mandate of chip design technology. At present, the technology used ARM Intellectual Property (IP) Core microprocessors, that is, we usually refer to as the ARM microprocessor, which cover the industrial control, and consumer electronic products, communications systems, network systems, wireless systems and other products market, Based on the ARM microprocessor technology application was about a 32-bit RISC microprocessor 75% above the share of the market, ARM technology is gradually infiltrated into our lives in various areas.ARM company specializing in technology-based RISC chip design and development company, as a supplier of intellectual property rights, it should not be directly involved in the production of silicon chips Design permits through the assignment of cooperation from the production company of special chips, the world's major semiconductor manufacturers from the company to buy its ARM microprocessor design nuclear, According to different application areas, to add appropriate external circuit, thereby forming its own ARM microprocessor chip market. Currently, there are dozens of the world's largest semiconductor companies are using mandate of ARM, So not only makes ARM technology to get more third-party tools, manufacture, the support of the software, so that the whole system can reduce costs, make our products more easily enter the market to be acceptable by consumers and more competitive.3 ARM microprocessor application areas and features3.1 ARM microprocessor application areasSo far, the ARM microprocessor technology and the application almost went to various areas :1. Industrial control areas: as a 32 bit RISC structure, ARM-based microcontroller chips will occupy the high-end micro-controller market most of the market share. also gradually to the low-end micro-controller applications expansion, ARM microcontroller with low power consumption, high performance-cost ratio. And give a challenge to traditional 8 / 16 Microcontrollers.2. The wireless communications field : At present, more than 85% of wireless communications equipment used ARM technology, ARM with high performance and low cost in the area of the increasing consolidation.3. Network applications : As the technology promotion, ARM technology using ADSL chip is gradually gaining competitive advantage. In addition, the ARM in voice and video processing uplink optimization, and is widely supported, DSP is also the right application areas posed a challenge.4. Consumer electronics products : ARM technology in the popular digital audio player, Digital Set-Top-Box and games were used extensively.5.Imaging and security products : the now popular digital cameras and printers used most of the ARM technology. The mobile phone SIM 32 smart cards are using ARM technology.In addition, the ARM microprocessor and technology has been applied to many different fields, and in the future will be more widely used.3.2 Features of the ARM microprocessorARM microprocessor using ARM RISC microprocessor architecture generally as Under characteristics :1. Small size, low power, low cost, high performance;2. Support Thumb (16) / ARM (32) - instruction set, Compatibility can be a very good 8 / 16 devices;3.The extensive use of registers, the directive is faster;4. Most data operations are completed by the middle of the Register;5. Addressable flexible simple, high efficiency;6. Fixed length instructions;3.3 ARM microprocessorARM microprocessor series currently includes the following several series, and other manufacturers based on the ARM architecture processors, in addition to ARM architecture a common feature, Every one of a series of ARM microprocessors have their own characteristics and application areas.-Series ARM7-Series ARM9-series ARM9E-ARM10E Series-SecurCore series- The X scale Inter-StrongARM of InterARM7, ARM9, ARM9E, and ARM10 of four generic processor series, each series provides a unique set of comparative performance to meet the needs of different areas of application needs. SecurCore series of specialized security requirements for the application of high design.We can find out in detail the characteristics of various processors and application areas.3.3.1 The series of ARM7 microprocessorARM7 series of low-power microprocessors for the 32 RISC processor, the most suitable for the right price and power consumption demand higher consumer applications. ARM7 microprocessor series has the following characteristics :-Embedded ICE-RT logic, developed to facilitate debugging.-Very low power consumption, suitable for higher power applications, such as portable products.- Able to provide the three pipeline structure by 0 .9MIPS/MHz.-Code compatibility and high density of 16 Thumb instruction set. - Right to support a broad range of operating systems, including Windows CE, Linux, Palm OS, and so on.-Instruction System and ARM9 series, ARM9E and ARM10E series compatible series, user-friendly to the upgrading of products.-The frequency of up to 130 MIPS, high-speed computational processing capacity will rise tothe majority of the complex application.ARM7 microprocessor series of the main application areas : industrialcontrol, Internet equipment, network and modem equipment, mobile phones and other multimedia and embedded applications.ARM7 microprocessor series include several types of nuclear : ARM7TDMI, ARM7TDMI-S, ARM720T, ARM7EJ. Among them, ARM7TMDI is currently the most widely used 32-bit embedded RISC processor, ARM is a low-end processor core. TDMI the basic meaning : T : Support for 16 compression Thumb instruction set;D : Support on-chip Debug;M : Embedded hardware multiplier (Multiplier);I : Embedded ICE support on-chip breakpoints and debug.3.3.2 SecurCore microprocessorsSecurCore microprocessors E Series For safety needs, and provide a perfect 32-bit RISC technology security solutions, therefore, SecurCore addition to a series of ARM microprocessor architecture and low power consumption, high performance features, also has its unique advantage, namely to provide the right security solution for their support.SecurCore addition to a series of ARM microprocessor architecture major characteristics, Security also has the following characteristics :- With a flexible protective unit, to ensure that the operating system and application of data security.-Soft-core technology, to prevent its external scanning detection.-Users can be their own integrated security features and other coprocessor.SecurCore series microprocessors will be used in some of the higher security requirements of products and applications systems, such as e-commerce, e-government, e-banking business, network and certification systems, and other fields.SecurCore series contains SecurCore SC100 microprocessor, SecurCore SC110. SecurCore SC200 and SC210 SecurCore four types, applied to different applications.3.3.3 StrongARM microprocessorInter StrongARM SA -1100 ARM processor is used Architecture highly integrated 32-bit RISC microprocessor. It combines the Inter companies in the design and processing technology, and ARM Architecture power efficiency, use the software compatibility ARMv4 architecture,using Intel technology with the advantages of Architecture.Intel StrongARM processor is a portable communications products and consumer electronics products the ideal choice, has been successfully applied to a number of companies in the handheld computer series products.3.3.4 Xscale processorXScale processor is based on the ARMv5TE Aggregate structure of the solution is one the whole performance, high cost performance, low-power processor. It supports 16 of the Thumb instructions and DSP instruction set, used in digital mobile phones, Personal Digital Assistant and networking products, and other occasions.Inter Xscale processor is currently one of the main promotional ARM microprocessor.4Structure4.1 ARM RISC microprocessor architectureCISC (Complex Instruction Set Computer, complex instruction set computer) structure have inherent shortcomings, With the computer technology that is the development and introduction of new and complex instruction set to support these new directives, Computer architecture will be increasingly complex, but the CISC instruction set of instructions, their frequency of use is a difference of the poor, about 20% of the directive will be used repeatedly, the entire procedure for the 80% code. And the remaining 80% of the directive is not frequently used in the process is a mere 20%, it is clear that This structure is not very reasonable.Based on the above unreasonable, 1979 University of California at Berkeley, a RISC (Reduced Instructi on Set Computer, reduced instruction set computer) concept, RISC is not simply to reduce orders but putting the focus on how to make computer more simple structure raised to a reasonable computation speed. RISC structure preferred to use the highest frequency of simple instructions to avoid complicated instructions; Fixed length instructions. Directive format and find ways to reduce the types; to the main control logic. Avoid using micro-code control measures to achieve the above purpose.So far, the RISC architecture is also no strict definition, it is generally believed that, RISC architecture should have the following characteristics :- The use of fixed-length format of the instructions, directives to the whole, simple,Addressing a basic form 2 ~ 3.-The use of single-cycle instructions to facilitate the implementation of pipeline operation.-Extensive use of register data processing instructions only to register for operations, Only load / store instructions access memory, in order to improve the efficiency of enforcement.In addition, the ARM architecture also uses a special technology, ensure high performance under the premise of minimizing chip area, and lower power consumption :- All available under the directive before deciding whether to implement the results were executed, thereby improving the efficiency of instruction.-Can be used to load / store instructions batch transmission of data, to improve data transmission efficiency.- In a data processing instructions in parallel processing and shift logic processing.- Cycles in the use of the automatic address changes to improve operating efficiency.Of course, the structure and CISC, compared to RISC structure despite these advantages, But never RISC framework that can replace the CISC structure, in fact, RISC and CISC different advantages, but not so obvious boundaries.Modern CISC CPU often use the external and internal to the RISC characteristics, As long CPU instruction set is the integration of RISC and CISC advantages, become the future development direction of one of the CPU.4.2 ARM microprocessor structureARM processor register a total of 37 registers, divided into a number of groups (BANK), which registers include :-31 Universal Register, including procedures Counter (PC pointer), both of the register 32.-6 state register, to mark the work of the CPU state and the procedures of the operations, both 32. Currently used only in part.Meanwhile, ARM processor has seven different types of processor model In each processor model has a corresponding group with the corresponding register. In an arbitrary processor model, visit the Register, including 15 general registers (R0 - R14), 1-2 state register and procedures counter. Register in all, some of the seven types of processor model with a shared physical register, Some of the register is different processors under different models of the physical register.ARM processor on the Register, the structure behind the relevant sections will be described in detail.4.3 Instructions structure of ARM microprocessorARM microprocessor in the newer architecture support Two Instruction Set : ARM instruction set and Thumb instruction set. Among them, ARM instructions to the 32 length Thumb instructions for 16 length. Thumb instruction set for the ARM instruction set subset of the functions, but with the equivalent ARM code comparison, save 30% ~ 40% more storage space, while 32 have all the advantages of code.On the ARM processor instructions, the structure behind the relevant sections will be described in detail. ARM microprocessor5Selection of ARM microprocessorARM microprocessor light of the many advantages Following the field of embedded application development, the ARM microprocessor will receive wide attention and application. However, the ARM microprocessor, as many as 10 several kernel structure, dozens of chip manufacturers. and a variety of internal functional configuration, to the development staff in the selection of programs bring some difficulties, so ARM chips to do some comparative study is very necessary.Flowing is the application point of view. The ARM microprocessor options to be considered when the main issues of some brief.ARM microprocessor core from the choice earlier on the contents showed that ARM microprocessor contains a series of core structures to suit different application areas, If users want to use WinCE or standard Linux operating system to reduce software development time, ARM720T need more choices with MMU (Memory Management Unit ) functional ARM chips, ARM720T, ARM920T, ARM922T, ARM946T, Strong-ARM has the MMU function. ARM7TDMI and MMU is not, and will not support the standard Windows CE and Linux. But there are currently no such uCLinux MMU support of the operating system can run on hardware-ARM7TDMI Taiwan above.In fact, uCLinux has been successfully transplanted to a variety of non - MMU's microprocessor platform. and the stability and other aspects of good performance. The book under discussion S3C4510B section shall be non - MMU ARM microprocessor, in their running uCLinux operating system. The frequency of the system frequency in a large extent determine the ARM microprocessor-handling capacity.ARM7 microprocessor series of typical processing speed of 0 .9MIPS/MHz. common ARM7chip system main clock 20 MHz-133 MHz, ARM9 microprocessor series of typical processing speed for a .1MIPS/MHz. common ARM9 main system clock frequency of 100 MHz-233MHz. ARM10 can reach 700 MHz. Different clock chip to handle different, and some chips need only one main clock frequency, Some chip controller can be internal clock for ARM core and USB, UART, DSP, Audio functions such as providing different frequency components of the clock.Chip memory capacity of most of the ARM microprocessor chip memory capacity not too much, users need in the design of the system memory expansion outside, but there were also some chip with a relatively large chip storage space, If the AT91F40162 on A TMEL has reached 200 MB of memory chip procedures space, users may consider when designing this type chosen to simplify system design.Chip peripheral circuits in addition to the choice of nuclear ARM microprocessor, Almost all the ARM chip is based on different application areas, the expansion of the related functional modules, and integrated into the chip, we call on chip peripheral circuits, such as USB, IIS interface, LCD controller, keyboard interface, RTC, ADC and DAC, DSP coprocessor, system designers should analyze the demand, maximize the use of chip peripheral circuits necessary to complete the function, which could simplify the system design, improve the reliability of the system.第一章微处理器介绍及其发展1.1 微处理器的历史第一个微处理器最初是为计算机开发的，但它是那个时代的革命，在这个4位的微处理器上包含2300个晶体管，每秒钟可以执行将近6万个指令。
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Introductions of PLC and MCUA PLC is a device that was invented to replace the necessary sequential relay circuits for machine control. The PLC works by looking at its inputs and depending upon their state, turning on/off its outputs .The user enters a program, usually via software or programmer that gives the desired results.PLC are used in many “real world” applications. If there is industry present, chances are good that there is a PLC present. If you are involved in machining, packaging, material handling, automated assembly or countless other industries, you are probably already using them. If you are not, you are wasting money and time. Almost any application that needs some type of electrical control has need for PLC.For example, let’s assume that when a switch turns on we want to turn a solenoid on for 5 seconds and then turn it off regardless of how long the switch is on for. We can do this with a simple external timer. What if the process also needed to count how many times the switch individually turned on? We need a lot of external counters.As you can see, the bigger the process the more of a need we have for a PLC. We can simply program the PLC to count its inputs and turn the solenoids on for the specified time.We will take a look at what i s considered to be the “top 20” PLC instructions. It can be safely estimated that with a firm understanding of there instructions one can solve more than 80% of the applications in existence.That‘s right, more than 80%! Of course we’ll learn more than jus t these instructions to help you solve almost ALL your potential PLC applications.The PLC mainly consists of a CPU, memory areas, and appropriate circuits to receive input/output data, as shown in Fig. 19.1 We can actually consider the PLC to be a box full of hundreds or thousands of separate relays, counters, timer and date storage locations. Do these counters, timers, etc. really exist? No, they don’t “physically” exist but rather they are simulated and can be considered software counters, timers, etc. These internal relays are simulated through bit locations in registers.What does each part do?INPUT RELAYS-(contacts) These are connected to the outside world. They physically exist and receive signals from switches, sensors, etc... Typically they are not relays but rather they are transistors.INTERNAL UTILITY RELAYS-(contacts) These do not receive signals from the outside world nor do they physically exist. They are simulated relays and are what enables a PLC to eliminate external relays. There are also some special relays that are dedicated to performing only one task. Some are always on while some are always off. Some are on only once during power-on and are typically user for initializing data what was stored.COUNTERS These again do not physically exist. They are simulated counters and they can be programmed to count pulses. Typically these counters can count up, down or both up and down. Since there are simulated, they are limited in their counting speed. Some manufacturers also include high-speed counters that are hardware based. We can think of these as physically existing. Most timers these counters can count up, down or up and down.TIMERS These also do not physically exist. They come in many varieties and increments. The most common type is an on-delay type. Other include off-delay and both retentive and non-retentive types. Increments vary from 1ms through 1s.OUTPUT RELAYS-(coil) These are connected to the outside world. They physically exist and send on/off signals to solenoids, lights, etc… They can be transistors, relays, or triacs depending upon the model chosen.DATA STORAGE-Typically there are registers assigned to simply store data. There are usually used as temporary storage for math or data manipulation. They can also typically be user power-up they will still have the same contents as before power war removed. Very convenient and necessary!A PLC works by continually scanning a program. We can think of this scan cycle as consisting of 3 important steps, as shown in Fig.19.2 There are typically more than 3 but we can focus on the important parts and not worry about the others. Typically the others are checking the system and updating the current and timer values.Step 1-CHECK INPUT STATUS-First the PLC takes a look at each input to determine if it is on or off. In other words, is the sensor connected to the first input on? How about the second input? How about the third…It records this data into its memory to be used during the next step.Step 2-EXECUTE PROGRAM-Next the PLC executes your program one instruction at a time. Maybe your program said that if the first input was on then it should turn on the first output. Since is already knows which inputs are on/off from the previous step, it will be able to decide whether the first output should be turned onbased on the state of the first input. It will store the execution results for use later during the next step.Step 3-UPDATE OUTPUT STSTUS-Finally the PLC updates the status of outputs. It updates the outputs based on which inputs were on during the first step and the results of executing your program during the second step. Based on the example in step 2 it would now turn on the first output because the first input was on and your program said to turn on the first output when this condition is true.After the third step the PLC goes back to step one and repeats the steps continuously. One scan time is defined as the time is takes to execute the 3 steps listed above. Thus a practical system is controlled to perform specified operations as desired.The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8Kbytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the industry-standard 80C51 instruction set and pin-out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications.The AT89S52 provides the following standard features: 8K bytes of Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator, and clock circuitry. In addition, the AT89S52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port, and interrupt system to continue functioning. The Power-down mode saves the RAM contents but freezes the oscillator, disabling all other chip functions until the next interrupt or hardware reset.Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can sink eight TTL inputs. When is written to port 0 pins, the pins can be used as high-impedance inputs.Port 0 can also be configured to be the multiplexed lowered address/data bus during accesses to external program and data memory. In this mode, P0 has internal pull-ups.Port 0 also receives the code bytes during Flash programming and outputs the code bytes during program verification. External pull-ups are required during program verification.Port 1 is an 8-bit bidirectional I/O port with internal pullups.The Port 1 output buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low will source current (I IL) because of the internal pull-ups.In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external count input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX).PLC和微处理器简介PLC(可编程逻辑控制器)是极限控制中为代替必要的继电器时序电路而发明的一种设备。