Three aspects of RS 485 application, which affect the reliability of communication of data system are analyzed and discussed. In network configuration, it presents the optimal configuration for the bus of RS 485, the ...Three aspects of RS 485 application, which affect the reliability of communication of data system are analyzed and discussed. In network configuration, it presents the optimal configuration for the bus of RS 485, the better rule for derivative line and the choice for termination. In hardware design, it presents three parts of driver’s peripheral circuit. In control software design, it presents a method of using 75176’s DE line to control the driver.展开更多
Power loss sometimes needs particular consideration in coal mine. This paper analyzes the main three parts of power consuming of RS 485 system, that is quiescent power consuming, transmission power consuming and perip...Power loss sometimes needs particular consideration in coal mine. This paper analyzes the main three parts of power consuming of RS 485 system, that is quiescent power consuming, transmission power consuming and peripheral equipment power consuming. How to reduce the power consuming in RS 485 designs is introduced, and also the method of hardware and software design is presented including choosing low power transceiver, optimizing communication data structure, optimizing communication working mode.展开更多
With principles of reliability, independence, practicality and economical effi- ciency, a set of intelligent fire alarm system based on AVRmega128 single chip microcomputer was designed to solve problems of fire alarm...With principles of reliability, independence, practicality and economical effi- ciency, a set of intelligent fire alarm system based on AVRmega128 single chip microcomputer was designed to solve problems of fire alarm system in many large- scale warehouses. Using advanced flame sensor, 485 bus communication, computer interactive software and related peripheral devices, this intelligent fire alarm system has functions of sound-light alarm and intelligent fire extinguishing. The human-com- puter interactive software was adopted for the remote control of the alarm main control panel through the 485 bus communication. This design of intelligent fire alarm system shows high reference and practical value to the development of intel- ligent alarm products with high integration and high reliability.展开更多
This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-s...This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-ship and parameters, and data processing and transmission,mission calculation, graphical supervision and gunnery ballistics outputting. The simulation systemis able to receive instruction from, or send information to the command-control center. Furthermore,the system can also be used to compare various designed schemes and analyze the accuracy andeffectiveness of the system.展开更多
Combined with the engineering requirement, a high-speed low-power ASIC design of HDLC controller based on RS-485 bus is given in this paper. On principle of Top-Down design, this ASIC design uses multi-techniques to r...Combined with the engineering requirement, a high-speed low-power ASIC design of HDLC controller based on RS-485 bus is given in this paper. On principle of Top-Down design, this ASIC design uses multi-techniques to reduce its die area and dynamic power, and overcomes some problems appeared frequently in application systems of the RS-485 circuits formed by the Standard Interface Chips. This design also improves the system reliability and reduces the system area.展开更多
This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are c...This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are connected on the 1-wire bus together. RS-485 master-slave communication protocol is used to centralize monitoring temperatures of several switchgear cabinets. The system also has the function of temperature alarm. The operation of simulation experiment has showed that the system is able to complete monitoring real-time temperatures in high voltage switchgear.展开更多
This paper briefly analyzes the present situation of textile mill＇s air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill＇s airconditioning system because of the i...This paper briefly analyzes the present situation of textile mill＇s air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill＇s airconditioning system because of the influence of various factors such as the differences in seasons, regions, etc., most air-conditioning equipment can not be controlled automatically. This paper suggests utilizing multi-function data acquisRion card to collect the data about the temperature and humidity of a workshop, processing the data on a PC, comparing them with the expert database, and then using the 485 serial port expanding module to output the parameters, which are used to control the inverter, so that the purpose of adjusting the temperature and humidity of the workshop is achieved.展开更多
In order to accurate measure micro displacement, the paper presents an accurate measuring system of distributed micro displacement. The system uses a linear CCD and FPGA and network communication technology to realize...In order to accurate measure micro displacement, the paper presents an accurate measuring system of distributed micro displacement. The system uses a linear CCD and FPGA and network communication technology to realize data acquisition and remote transmission. The test results show that the system can support 16 line array CCD test node to measure the micro deformation of the one- dimensional, the CCD data transmission rate is 3200 frames/s, node data transmission distance is greater than 200 m, and measurement accuracy is 500 micron.展开更多
This paper proposes a redundant network communication structure for the patient integrated circuit(IC)card payment system in a hospital information system(HIS),compares it with the network structure of normal hospital...This paper proposes a redundant network communication structure for the patient integrated circuit(IC)card payment system in a hospital information system(HIS),compares it with the network structure of normal hospital IC card system,and calculates the reliabilities of the related communications like the RS485communication and the Ethernet communication.The new structure can efectively promote the reliability of the hospital operation and ensure the payment collection when the Ethernet network is broken.The system is applied to a local hospital and the cost-performance rate is satisfactory during the application.展开更多
文摘Three aspects of RS 485 application, which affect the reliability of communication of data system are analyzed and discussed. In network configuration, it presents the optimal configuration for the bus of RS 485, the better rule for derivative line and the choice for termination. In hardware design, it presents three parts of driver’s peripheral circuit. In control software design, it presents a method of using 75176’s DE line to control the driver.
文摘Power loss sometimes needs particular consideration in coal mine. This paper analyzes the main three parts of power consuming of RS 485 system, that is quiescent power consuming, transmission power consuming and peripheral equipment power consuming. How to reduce the power consuming in RS 485 designs is introduced, and also the method of hardware and software design is presented including choosing low power transceiver, optimizing communication data structure, optimizing communication working mode.
基金Supported by the National Natural Science Foundation of China(11275164)~~
文摘With principles of reliability, independence, practicality and economical effi- ciency, a set of intelligent fire alarm system based on AVRmega128 single chip microcomputer was designed to solve problems of fire alarm system in many large- scale warehouses. Using advanced flame sensor, 485 bus communication, computer interactive software and related peripheral devices, this intelligent fire alarm system has functions of sound-light alarm and intelligent fire extinguishing. The human-com- puter interactive software was adopted for the remote control of the alarm main control panel through the 485 bus communication. This design of intelligent fire alarm system shows high reference and practical value to the development of intel- ligent alarm products with high integration and high reliability.
文摘This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-ship and parameters, and data processing and transmission,mission calculation, graphical supervision and gunnery ballistics outputting. The simulation systemis able to receive instruction from, or send information to the command-control center. Furthermore,the system can also be used to compare various designed schemes and analyze the accuracy andeffectiveness of the system.
文摘Combined with the engineering requirement, a high-speed low-power ASIC design of HDLC controller based on RS-485 bus is given in this paper. On principle of Top-Down design, this ASIC design uses multi-techniques to reduce its die area and dynamic power, and overcomes some problems appeared frequently in application systems of the RS-485 circuits formed by the Standard Interface Chips. This design also improves the system reliability and reduces the system area.
文摘This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are connected on the 1-wire bus together. RS-485 master-slave communication protocol is used to centralize monitoring temperatures of several switchgear cabinets. The system also has the function of temperature alarm. The operation of simulation experiment has showed that the system is able to complete monitoring real-time temperatures in high voltage switchgear.
文摘This paper briefly analyzes the present situation of textile mill＇s air-conditioning system. Since it is difficult to establish detailed math model to control a textile mill＇s airconditioning system because of the influence of various factors such as the differences in seasons, regions, etc., most air-conditioning equipment can not be controlled automatically. This paper suggests utilizing multi-function data acquisRion card to collect the data about the temperature and humidity of a workshop, processing the data on a PC, comparing them with the expert database, and then using the 485 serial port expanding module to output the parameters, which are used to control the inverter, so that the purpose of adjusting the temperature and humidity of the workshop is achieved.
文摘In order to accurate measure micro displacement, the paper presents an accurate measuring system of distributed micro displacement. The system uses a linear CCD and FPGA and network communication technology to realize data acquisition and remote transmission. The test results show that the system can support 16 line array CCD test node to measure the micro deformation of the one- dimensional, the CCD data transmission rate is 3200 frames/s, node data transmission distance is greater than 200 m, and measurement accuracy is 500 micron.
基金the National Natural Science Foundation of China(No.81170507)the Project of Shanghai Committee of Science and Technology(Nos.11140903700 and 12142201200)
文摘This paper proposes a redundant network communication structure for the patient integrated circuit(IC)card payment system in a hospital information system(HIS),compares it with the network structure of normal hospital IC card system,and calculates the reliabilities of the related communications like the RS485communication and the Ethernet communication.The new structure can efectively promote the reliability of the hospital operation and ensure the payment collection when the Ethernet network is broken.The system is applied to a local hospital and the cost-performance rate is satisfactory during the application.
