论文中英文翻译(原文)
编号：
桂林电子科技大学信息科技学院
毕业设计(论文)外文翻译
（原文）
系别：电子工程系
专业：电子信息工程
学生姓名：韦骏
学号：0852100329
指导教师单位：桂林电子科技大学信息科技学院姓名：梁勇
职称：讲师
2012 年6 月5 日
Design and implementation of the agreement based on embedded system Modbus Linux
Abstract: with the embedded with the rapid development of computer technology, a new generation of industrial automation data acquisition and monitoring system, adopting the core of high performance embedded microcontroller processor, the system well adapt to the application. It is in line with strict requirements of consumption and other functions, such as reliability, the cost, size and power consumption, etc. In the industrial automation application system, Modbus communication protocol industrial standard, widely applied in large scale industrial equipment system, including DCS, PLC, RTU and intelligent instruments, etc. In order to achieve embedded data monitoring of industrial automation software application needs, this paper designed the embedded data acquisition monitoring the workbench Modbus agreement based on the Linux environment collection system. The serial port is to realize the
master/Modbus agreement from type, including two kind of communication mode: ASCII and RTU. Therefore, all kinds of ointment agreement can meet the Modbus equipment serial communication. In the embedded platform Modbus agreement steady and reliable. It in embedded data monitoring automation of the application system of new acquisitions prospect. Keywords: embedded system, embedded Linux, Modbus agreement, data acquisition and monitoring and control.
1, the introduction
Modbus is a communication protocol, is a company by MoDiKang promotion. It is widely used in industrial automation, has become a real industry standard. The control device or different manufacturer measuring instrument can link to an industry monitoring network use Modbus agreement. Modbus communication protocol can serve as a lot of industrial equipment communication standards, including PLC, DCS system, RTU, intelligent intelligent instrument. Embedded with the rapid development of computer technology, embedded data acquisition monitoring system, using the embedded
high-performance microprocessors as the core, is an important development direction. In the environment of Linux embedded in view of the application of the embedded industrial automation data, a Modbus Lord agreement collection monitoring system design and the realization of the document. Therefore, communication equipment, various ointment agreement can meet the serial Modbus.
2, Modbus agreement profile
Modbus agreement including ASCII, RTU and TCP transfer mode, support the traditional RS-232 and RS-422, RS-485 and Ethernet equipment. As for the serial port Modbus equipment, controller, in standard Modbus network protocol can be based on two transmission mode: ASCII mode or RTU mode. As for Ethernet Modbus equipment, transfer mode is Modbus/TCP protocol. The same transport model and parameters must choose on the network of all equipment Modbus. Modbus agreement is independent of hardware. Instead, the physical layer, it only defines the structure of data, the controller can distinguish. However, network communication is not defined. Modbus agreement stipulated the information and data
structure, command and response way. The agreement to the Lord to/from method is used to data communication. A host of the request of the information, and the response from the machine and the Lord returns to the correct information of information in response to request to receive. Host can also sends messages to modify the data from the machine.
Modbus agreement need validation data. Serial protocol has check, in addition, ASCII mode to use LRC check, RTU mode and use 16 CRC checking. But, no additional provisions TCP mode examinations, because the TCP protocol is a reliable agreement, and face a connection. In addition, the use of Modbus master-slave way, sending and receiving fixed time in the material. In practice, if some affiliate equipment separate, Lord can be diagnosed it, fault be repaired, the network can automatic connection. Therefore, Modbus agreement is reliable. Because the news of Modbus agreement structure, each controller need a device address, this is used to distinguish between news and the judge will take some actions. If the response is necessary, controller will produce the reply and Modbus agreement transmitted to one side of the inquires. The design of the system it is embedded data acquisition system of the overall structure. In this system, embedded data acquisition platform is the core and the control equipment data communication and embedded data acquisition platform of the agreement from station Modbus Modbus through various. Therefore, data collection, data analysis, through the TCP/IP is to realize the pretreatment of data transmission to the operator and engineers monitoring center. Industrial microprocessor Atmel company is the AT91RM9200 as embedded data acquisition of the core of the platform. In embedded data acquisition platform integrating different surrounding connection in addition, including a serial port, CAN bus interface, will make the AD/DA interface RS485 interface, SD/MMC card for reading and writing, JTAG and debugging debugging interface, 18 inches TFT true color LCD screen, it CAN in data may be used for demonstration, also has the function of the touch screen, and integration in this platform. Embedded Linux operating systems use embedded data acquisition platform, and Modbus agreement can realize the function. Therefore, embedded platform, we can read the agreement through a serial port Modbus the slave's data, and displayed on the LCD (touch screen) is processed, analysis and data. At the same time, can transmit data, through the Ethernet interface embedded platform, for further the monitoring and management of the monitoring center after analysis and processing.
4, design and Modbus agreement under the environment of embedded Linux implementation
4.1, embedded Linux system and transplantation with the development direction of Linux, one of many successful and embedded Linux mature product. Stability, reliability and high efficiency of the embedded Linux is proof that the facts. Embedded Linux open source code, to provide technical support, has good expansibility widely, support a variety of hardware. All of these are the embedded Linux advantage. The system USES the embedded hardware environment for Linux operating system and ARM9. At present, the ARM of a series of Linux support ARM processor, including ARM610, ARM710,
ARM720Tcores, ARM920Tcores, StrungARM110, SrtongARM1100, XScale and etc of the board
AT91RM9200 Atmel is the use as the goal, in this file. Different from the standard Linux, it must start from the flash memory or ROM. The United States start used as this paper start programs. In order to hand transplant Linux operating system, it also needs to all kinds of resources Linux drivers. If the equipment is by their own design, and it need to write the corresponding driver. Linux the general procedure of the transplant as shown in figure 2. As for the ARM kernel file system and Linux, u-boot is through a serial port first downloaded to the development board, then use a serial port or network method. Because the kernel and the file system is a reflection of the large files through the serial port transmission speed slow; Ethernet mode for downloading the kernel and the file system. Of course, the network U-Boot parameters need to be in before download process. According to the established the u-boot command mode the u-boot network parameters: the TFTP server is running in service, and then compile the kernel file system and image image is added to the server directory. Server and network development board and cable connection, and then, the kernel and download to system memory through the running start under the command line under the orders of the u-boot: the compiled Linux can operation after the arm bootm 21000000. The kernel and file system memory can through to the order of the director of flash start u. The system can automatically after the operation, set start parameters. Then program operation development board.
In 4.2, a serial configuration of Modbus protocol in the Linux environment standard Modbus serial protocol using RS232/RS485 transmission. Serial device device nodes for
/dev/ttyS0( COM1dev/ttyS1COM2) Linux port ) port environment. And / ( in as Modbus serial protocol includes two kinds of transmission mode and RTU mode: ASCII. Start and end tags of the two models are different. In addition, each information packet data in different position. Therefore, must be handled individually. Using RTU model as an example, introduced in the Linux environment Modbus serial protocol configuration. Header files by serial operation need is: when the characteristic of Modbus protocol is the use of RTU transmission mode, the serial baud rate, data bits, stop position, check the position and control should be set according to the features of the framework of the information. Set serial port baud rate: in the design, in order to make its get convenient. Function parameters, is the definition of a structure such as a slave_address is from the station address. A Modbus network allows up to255 from the station. The function is service mode selection characteristics, and there are six kinds of service mode in this system is provided, respectively 1-6. The start_address is a 16bit character, it is present from the start address of station power supply equipment. The pointnum_or_setdata includes2 languages,1-4is nodded to increase the number of business services, services 5and 6 are16 characters being established. The programme was first identified format character value, establishes the transmission mode, the user needs, which will determine which serial configuration function and service function of what choice. Then set the serial port parameters in Linux environment. The corresponding service structure function is adopted to judge whether a user request type of service selection. For example, if the format is 0, with RTU mode. The function is 1, this means the user request read coil. The program by using the construct_rtu_frm constructor is the
rtu_read_status function calls Modbus request frame. The program retained the serial transmission buffer mod_tx_buf, this is defined it, then put through the call command Modbus serial transmission request frame. If the program setting the time response frame, the programme will reply to handle frame by calling a corresponding mode of analytic functions. For example, when is ASCII transmission mode, the
ascii_data_anlys function is called, if the transmission mode is a mode of RTU, then rtu_data_anlys is called. Analytic function analysis of the data, the receive buffer receives the serial. If the reply frame analysis is correct, the function of loading data to target buffer. If it is wrong, the function will stop this service, and handling errors, print error message.
In 4.3, Modbus protocol serial software design
This paper introduces the design and Realization of serial Modbus protocol, which includes two kinds of transmission mode of RTU and ASCII. In the Modbus hosting service including a man-machine interaction module, function module, function module and return processing module. Each module's function is realized in the embedded Linux environment. A man-machine interaction module is for the user and platform communication module. It mainly realized the webpage print function, the user information input and guidance. The function of the selection module is the main function of the Modbus platform selection selection of parameters according to user input information. These parameters include the dissemination way, service type, from the station address. The function processing module is the core of the platform. It includes serial initialization function, structure of the Modbus frame, modal analysis of Modbus frame, all kinds of business processing and business processing and other6 major design, including: serial Modbus device in this platform reading coil state, read input status, read hold register, read input register, write, write single coil single registration. The 6model covers the Modbus basic function demand. And it is very convenient to extend, if necessary with other functions. Return processing module processes the results of operation platform. If the user requests a service process, service results will be through the standard output device, printing, or error messages.
4.4, service on the structure and function of analysis framework
To read hold register service as an example, introduces the construction requirement in the process of Modbus frame. The function to read the register number is03 and construction requirements of the Modbus frame is realized by rtu_read_hldreg and ascii_read_hldreg function. The former realizes RTU frame structure, and the latter ASCII frame structure. The rtu_read_hldreg structure is shown as follows: the input parameter board_adr is from the station address, the user needs to access. Is the com_buf buffer Modbus frame transmission field. The start_address is access to the starting address and length lenth is accessible. All of these variables, it is through the structural module parameters of human-computer interaction. High and low ( ) ( ) is a two defined function. The high ( ) is to achieve a high8, low ( ) is a low8bits. The construct_rtu_frm is the RTU frame structure. All services are by calling this function, formation of a RTU request frame. Its structure is as follows: after these steps, a frame request has been completed. Finally, in
order to write ( FD, mod_tx_buf, tx_len ) is invoked through the serial port to send and the transmission buffer requests Modbus frame transmission. Tx_len is a service where the service constructor return value. Request frame transmission, the program will wait from the station response. In order to avoid endless loop mechanism, through the detection from the station did not respond, the establishment of a working overtime. If the slave station and is not within the predetermined time response, program generated an error message and stop the service. If the service program at a predetermined time received the reply frame, analysed by calling the analytic function response time.
5, conclusion
Modbus communication protocol widely used, has become the industry standard, in fact. It is a heavily used industrial equipment as the communication between them standards, including DCS, programmable controller, RTU communications, smart instrumentation and monitoring system of a new generation of industrial automation data acquisition using high performance embedded microprocessor core. Therefore, it is suitable to application programs are well meet the functional, reliability, cost, volume, power and strict requirements, in order to achieve the embedded data monitoring in industrial automation applications, system acquisition requires Modbus protocol site embedded data acquisition monitoring Linux environment platform, is this design basis. Each slave station between the communication realization. According to the Modbus embedded Linux environment services running stable, reliable test, Modbus protocol. It provides good service to the Modbus master, and in accordance with the standard Modbus protocol. In the industrial automation data acquisition and monitoring system of a new generation of application prospect is very good.
In 6, thanks
This work supports a portion of the item by the Shanghai science and technology research projects ( No. 061111004), Shanghai dawn track program (06GG13) and Shanghai leading academic projects.
7, reference
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[2] Zhang Hao, Huangwoon Hiko, Peng Daogang. Study on the early warning system of EGI based on [J] Modbus protocol. Mechatronics,2007,13(2):15 -18.
[3] Li Juan, Zhang Bo, Qiu dongyuan. Multi machine communication with Modbus RTU is headquartered in power quality monitoring system [J]. Electric power automation equipment,2007,27, (1):93 -96.
[4] Yue Yang, Zhang Chunguang, Yuan Aijin. Design and implementation of embedded man-machine interface based on Modbus research [J]. Industrial control computer,2006,19(1):8 -10.
[5] Min Huasong, Liu Guanglin. Embedded state monitoring and fault diagnosis system of high speed rotating machinery research [J]. Information and control,2006,35(3):309 -313.
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Component-based Safety Computer of Railway Signal Interlocking System 1 Introduction Signal Interlocking System is the critical equipment which can guarantee traffic safety and enhance operational efficiency in railway transportation. For a long time, the core control computer adopts in interlocking system is the special customized high-grade safety computer, for example, the SIMIS of Siemens, the EI32 of Nippon Signal, and so on. Along with the rapid development of electronic technology, the customized safety computer is facing severe challenges, for instance, the high development costs, poor usability, weak expansibility and slow technology update. To overcome the flaws of the high-grade special customized computer, the U.S. Department of Defense has put forward the concept：we should adopt commercial standards to replace military norms and standards for meeting consumers’demand [1]. In the meantime, there are several explorations and practices about adopting open system architecture in avionics. The United Stated and Europe have do much research about utilizing cost-effective fault-tolerant computer to replace the dedicated computer in aerospace and other safety-critical fields. In recent years, it is gradually becoming a new trend that the utilization of standardized components in aerospace, industry, transportation and other safety-critical fields. 2 Railways signal interlocking system 2.1 Functions of signal interlocking system The basic function of signal interlocking system is to protect train safety by controlling signal equipments, such as switch points, signals and track units in a station, and it handles routes via a certain interlocking regulation. Since the birth of the railway transportation, signal interlocking system has gone through manual signal, mechanical signal, relay-based interlocking, and the modern computer-based Interlocking System. 2.2 Architecture of signal interlocking system Generally, the Interlocking System has a hierarchical structure. According to the function of equipments, the system can be divided to the function of equipments; the system
英语原文及翻译
高速视频处理系统中的信号完整性分析 摘要：结合高速DSP图像处理系统讨论了高速数字电路中的信号完整性问题，分析了系统中信号反射、串扰、地弹等现象破坏信号完整性的原因，通过先进IS工具的辅助设计，找出了确保系统信号完整性的具体方法。 关键词：高速电路设计信号完整性 DSP系统 深亚微米工艺在IC设计中的使用使得芯片的集成规模更大、体积越来越小、引脚数越来越多；由于近年来IC工艺的发展，使得其速度越来越高。从而，使得信号完整性问题引起电子设计者广泛关注。 在视频处理系统中，多维并行输入输出信号的频率一般都在百兆赫兹以上，而且对时序的要求也非常严格。本文以DSP图像处理系统为背景，对信号完整性进行准确的理论分析，对信号完整性涉及的典型问题[1]——不确定状态、传输线效应、反射、串扰、地弹等进行深入研究，并且从实际系统入手，利用IS仿真软件寻找有效的途径，解决系统的信号完整性问题。 1 系统简介 为了提高算法效率，实时处理图像信息，本图像处理系统是基于DSP+FPGA结构设计的。系统由SAA7111A视频解码器、TI公司的TMS320C6701 DSP、Altera公司的EPlK50QC208 FPGA、PCI9054 PCI接口控制器以及SBRAM、SDRAM、FIFO、FLASH等构成。FPGA是整个系统的时序控制中心和数据交换的桥梁，而且能够对图像数据实现快速底层处理。DSP是整个系统实时处理高级算法的核心器件。系统结构框图如图1所示。 在整个系统中，PCB电路板的面积仅为15cm×l5cm，系统时钟频率高达167MHz，时钟沿时间为0．6ns。由于系统具有快斜率瞬变和极高的工作频率以及很大的电路密度，使得如何处理高速信号问题成为一个制约设计成功的关键因素。 2 系统中信号完整性问题及解决方案 2．1 信号完整性问题产生机理 信号的完整性是指信号通过物理电路传输后，信号接收端看到的波形与信号发送端发送的波形在容许的误差范围内保持一致，并且空间邻近的传输信号间的相互影响也在容许的范围之内。因此，信号完整性分析的主要目标是保证高速数字信号可靠的传输。实际信号总是存在电压的波动，如图2所示。在A、B两点由于过冲和振铃[2]的存在使信号振幅落入阴影部分的不确定区，可能会导致错误的逻辑电平发生。总线信号传输的情况更加复杂，任何一个信号发生相位上的超前或滞后都可能使总线上数据出错，如图3所示。图中，CLK为时钟信号，D0、D1、D2、D3是数据总线上的信号，系统允许信号最大的建立时间[1]为△t。在正常情况下，D0、D1、D2、D3信号建立时间△t1<△t，在△t时刻之后数据总线的数据已稳定，系统可以从总线上采样到正确的数据，如图3(a)所示。相反，当信号D1、D2、D3受过冲和振铃等信号完整问题干扰时，总线信号就发生
科普版英语六年级下册课文及翻译 (直接打印版)
Lesson 1 I’m not feeling well. Let’s talk （M=Mom, T= Tom） M: What,'s the matter, Tom T: I'm not feeling well, Mom M: Do you have a cold T: Yes, I think so. Could you give me some water, please M: Here you are. T: Thank you, Mom. M: Tom, you must go and see a doctor. T: OK, Mom. M: It's cold outside. You must wear your coat. T: OK, Mom. Could you pass me my coat,please M: Here you are. T: Thank you, Mom M: Tell me your teacher's number. I'll call him and tell him you are sick. T: OK. Here it is. 译文 (M=妈妈,T=汤姆) 妈妈:怎么了,汤姆 汤姆:我感觉不舒服,妈妈。 妈妈:你感冒了吗 汤姆:是的,我想是这样的。您能给我一些水吗 妈妈:给你。 汤姆:谢谢您,妈妈。 妈妈:汤姆,你必须去看医生. 汤姆:好的,妈妈。 妈妈:外面很冷。你必须穿你的外套。 汤姆:好的,妈妈。您能把我的外套递给我吗 妈妈:给你。 汤姆:谢谢您,妈妈。 妈妈:告诉我你老师的电话号码。我将给他打电话告诉他你生病了。
毕业论文英文参考文献与译文
Inventory management Inventory Control On the so-called "inventory control", many people will interpret it as a "storage management", which is actually a big distortion. The traditional narrow view, mainly for warehouse inventory control of materials for inventory, data processing, storage, distribution, etc., through the implementation of anti-corrosion, temperature and humidity control means, to make the custody of the physical inventory to maintain optimum purposes. This is just a form of inventory control, or can be defined as the physical inventory control. How, then, from a broad perspective to understand inventory control? Inventory control should be related to the company's financial and operational objectives, in particular operating cash flow by optimizing the entire demand and supply chain management processes (DSCM), a reasonable set of ERP control strategy, and supported by appropriate information processing tools, tools to achieved in ensuring the timely delivery of the premise, as far as possible to reduce inventory levels, reducing inventory and obsolescence, the risk of devaluation. In this sense, the physical inventory control to achieve financial goals is just a means to control the entire inventory or just a necessary part; from the perspective of organizational functions, physical inventory control, warehouse management is mainly the responsibility of The broad inventory control is the demand and supply chain management, and the whole company's responsibility. Why until now many people's understanding of inventory control, limited physical inventory control? The following two reasons can not be ignored: First, our enterprises do not attach importance to inventory control. Especially those who benefit relatively good business, as long as there is money on the few people to consider the problem of inventory turnover. Inventory control is simply interpreted as warehouse management, unless the time to spend money, it may have been to see the inventory problem, and see the results are often very simple procurement to buy more, or did not do warehouse departments . Second, ERP misleading. Invoicing software is simple audacity to call it ERP, companies on their so-called ERP can reduce the number of inventory, inventory control, seems to rely on their small software can get. Even as SAP, BAAN ERP world, the field of
英文翻译原文
南京师范大学泰州学院 英文翻译原文 年级： 2011级学号：12110330 姓名：申佳佳 系部：信息工程学院 专业：通信工程 题目：基于C51的数字测速仪设计与仿真 指导教师：焦蓬蓬 2015 年 4 月 5 日
Linux - Operating system of cybertimes Though for a lot of people , regard Linux as the main operating system to make u p huge work station group, finish special effects of " Titanic " make , already can be re garded as and show talent fully. But for Linux, this only numerous news one of. Rece ntly, the manufacturers concerned have announced that support the news of Linux to i ncrease day by day, users' enthusiasm to Linux runs high unprecedentedly too. Then, Linux only have operating system not free more than on earth on 7 year this piece wh at glamour, get the favors of such numerous important software and hardware manufa cturers as the masses of users and Orac le , Informix , HP , Sybase , Corel , Intel , Net scape , Dell ,etc. , OK? 1.The background of Linux and characteristic Linux is a kind of " free (Free ) software ": What is called free, mean users can o btain the procedure and source code freely , and can use them freely , including revise or copy etc.. It is a result of cybertimes, numerous technical staff finish its research a nd development together through Inte rnet, countless user is it test and except fault , c an add user expansion function that oneself make conveniently to participate in. As th e most outstanding one in free software, Linux has characteristic o f the following: (1)Totally follow POSLX standard, expand the network operating system of sup porting all AT&T and BSD Unix characteristic. Because of inheritting Unix outstandi ng design philosophy , and there are clean , stalwart , high-efficient and steady kernels , their all key codes are finished by Li nus Torvalds and other outstanding programmer s, without any Unix code of AT&T or Berkeley, so Linu x is not Unix, but Linux and Unix are totally compatible. (2)Real many tasks, multi-user's system, the built-in n etwork supports, can be with such seamless links as NetWare , Windows NT , OS/2 , Unix ,etc.. Network in various kinds of Unix it tests to be fastest in comparing and ass ess efficiency. Support such many kinds of files systems as FAT16 , FAT32 , NTFS , E x t2FS , ISO9600 ,etc. at the same time .