介紹一種基于CAN總線的牽引變電站自動化系統通訊規約的設計，CAN通訊規約采用標準幀，報文采用主動發送和發送查詢兩種處理形式。該設計在城市輕軌與地鐵牽引變電站中的應用表明：可實現間隔層和通訊處理層的數據快速、可靠的交換，提高牽引變電站的安全性和穩定性 。 Abstract: This paper firstly presents a kind of design dealing with communicational protocol to the traction substation automation system based on CAN bus,and then comes up with the ideas that all frames of CAN communicational protocol should adopt the standard frame,and that messages be processed by two ways:sending initiatively and sending quiries.Subway and light rail application shows that the use of the CAN bus is possible to exchange data quickly and reliably between the layers of the middle and the communicational processing,hence to improve the safety and stability of traction substations.
上傳時間： 2013-11-07
上傳用戶：bs2005
介紹一種基于C8051F060單片機和NAND Flash的數據采集存儲系統，該系統可實現3路信號采樣，每路采樣率為5KS/s,通過異步串行通信接口實現數據傳輸。并詳細說明系統的軟件設計。 Abstract: An acquisition and storage system based on C8051F060and NAND Flash is designed in this paper.The system is used to sample three-channel of signal,5KSPS each channel,and can upload data to test bench through UART（Universal Asynchronous Receiver/Transmitter）.The software design is discussed in detail.
上傳時間： 2013-10-12
上傳用戶：Jesse_嘉偉
摘要：在工業自動控制中，單片機與PLC的遠距離通信是一個難點與熱點問題。本文設計了S7-200PLC與PIC16F877單片機實現遠距離串行通信的硬件連接和軟件實現方法。本文采用了MAX485E芯片進行TTL電平與差分信號之間的轉換，使用RS-485端口和半雙工模式進行通信。最后通過異或校驗碼對接收到的數據進行核對，以進一步提高數據傳輸的可靠性。實驗證明，該方法成功實現了單片機與PLC的遠距離通信，并且具有開發簡單，抗干擾能力強的特點，具有一定實用價值。關鍵詞：單片機 PLC 串行通信
上傳時間： 2014-12-27
上傳用戶：YUANQINHUI
介紹一種簡單射頻識別系統設計。該設計包括閱讀器、應答器和線圈3部分。由單片機控制閱讀器向應答器發射無線信號，并接收應答器回送的信號，再通過分析回送信號識別物品。閱讀器和應答器之間以半雙工通信方式通信。 Abstract: A simple design of radio frequency identification system is given in this paper.The design includes reader,responder and winding.Through MCU，signals are sent to responder from reader，then corresponding signals are sent back. According to the analysis of the signals sent back，the objects can be identified.Half-duplex communication is adopted? between? reader? and? responder.
上傳時間： 2013-10-11
上傳用戶：plsee
闡述了一個由上位PC機和AT89C52下位單片機組成的主從分布式溫度巡回檢測系統。主從機采用RS-485 串行通訊標準進行通信，可在下位單片機實現基本的溫度數據巡回檢測基礎上，由上位PC機實現綜合處理功能或擴展為遠程操作。整個系統具有巡檢速度快，擴展性好的特點。 Abstract: In this paper,a top PC and AT89C52 under-bit microcontrollers from the main component of the tour distributed temperature detection system is presented. Master and slave can use RS-485 serial communication standards for communications.Based on next-bit machine for basic goods temperature detected data Tour, the top can achieve the integrated treatment of PC functions or for the expansion of long-distance operation. The entire inspection system is fast, expansion.
上傳時間： 2013-10-13
上傳用戶：zhoujunzhen
在開放式數控系統結構模型的基礎上，研究了基于ISA總線的DSP通信控制原理。采用中斷方式完成了PC機和DSP之間的通信。介紹了以DriverWorks為工具開發ISA設備WDM驅動程序的方法，探討了中斷處理、驅動程序與應用程序之間的通信,簡要說明了驅動程序的安裝與調試。通過調試,系統設計運行穩定。 Abstract: The ISA bus and DSP correspondence control principle is investigated in the basis of the existing open architecture numerical control system.The interrupt method is used to realize the communication between PC and DSP based on the ISA bus.The methods of WDM driver exploitation for ISA device using Driver Works are introduced.The main process of driver program and the keys such as handle interrupt and the communication between the drivers and application are presented.And how to debug and install the drive is explained.
上傳時間： 2013-11-04
上傳用戶：kang1923
為滿足礦井安全生產要求，介紹了一種以AT89C51單片機為主控器，對環境空氣的溫度、有毒易燃氣體的濃度等進行檢測的監控系統。該系統配合外圍電路能實現對上述環境指標的控制并存儲相關數據與上位PC機通信。它采用硬件抗干擾和軟件抗干擾技術，以確保整個系統工作的準確性。 Abstract: In order to meet the needs of mine produce safety，a kind of intellignet mine ambient monotoring and control system based on AT89C51 is introduced.This system can detect the temperature of ambient of mine，the density of poisonous inflammable gas,combined external circuit.With its function part， this system can change above-mentioned elements.
上傳時間： 2013-11-10
上傳用戶：wendy15
為了解決磁放大器性能測試過程中，需要對其供給不同數值恒定電流的問題，設計了一種基于DAC7512和單片機的數控恒流源系統。該系統采用AT89C51作為主控器件，將計算機發送的電流控制字命令轉換為D/A轉換器控制字，通過模擬SPI通信接口，寫D/A控制字到DAC7512，從而控制其輸出相應數字電壓值，經差動縮放電路、電壓/電路變換電路和功率驅動電路，最后輸出恒定電流。實驗結果表明，恒流源輸出電流調節范圍為-45~+45 mA、精度為±0.1 mA，分辨率達0.024 4 mA，具有應用靈活，外圍電路簡單，可靠性高的特點。該數控直流恒流源也可為相關產品的測試系統研發提供參考。 Abstract: In order to solve the need to supply different values constant current for the magnetic amplifier in testing process， numerical control constant current source system was designed based on DAC7512 chip and microcontroller technology. The system used the AT89C51 as the main chip， which can convert the current control word from computer into to D/A control words. And the system wrote D/A control word into the DAC7512 chip to control the output voltage value by the SPI communication interface， which can output corresponding constant current figures by scaling circuit， the V/I converter and power drive circuit. Experimental results show that the current source output current adjustment range is -45~+45mA， accuracy is ± 0.1mA， and resolution ratio is 0.024 4mA
上傳時間： 2014-12-27
上傳用戶：invtnewer
以AVR單片機ATmega8和USB接口器件PDIUSBD12為核心，基于標準的USB1.1協議，設計一種通用USB接口模塊，以滿足嵌入式系統中對USB接口的需求。對模塊的硬件電路或單片機固件程序的硬件接口層稍加修改即可用于其他各種微處理器。該模塊可為各種嵌入式系統增加USB接口,實現與USB主機系統通信。 Abstract: Based on AVR microcontroller ATmega8 and USB interface chip PDIUSBD12, a general USB interface module is designed according to USB1.1 protocol for various requirements of embedded systems. Only with few modifications in circuit or hardware abstract layer of firmware, the module can be used on many types of microprocessors. All kinds of embedded systems can realize high speed and stable communication with USB host systems, owing to the facility of this module.
上傳時間： 2014-01-08
上傳用戶：趙云興
介紹了基于單片機C8051F020的通用串口適配器的設計與實現方法，即由單片機控制的智能化一對多口收發信號轉換器。通過采用C51對單片機進行編程，控制與RS-232（標準RS-232電平）、RS232(TTL電平)、RS-422接口的數據通信；采用C++ Builder作為開發平臺，通過RS-232接口實現上位機對適配器各個通信端口的控制。 Abstract: Design and realization of a universal serial port adapter based on the MCU C8051F020 are introduced.The adapter is an intelligent one-to-more receiving and transmitting signal converter controlled by the MCU. By programming the MCU with the language C51,MCU control data communication between the MCU and RS-232(RS-232 level),RS-232(TTL level),RS-422 port; Using C++ Builder as the development plane, by one RS232 port, the upper PC can control each of the communication port of the adapter.
上傳時間： 2013-11-19
上傳用戶：hebanlian
