對于瀝青混凝土攤鋪機自動找平控制系統來說，數字式控制系統的研制是目前的一個方向。介紹了一種基于CAN總線的數字式自動找平控制系統。該系統以CAN總線作為通信方式，PWM控制信號通過C8051F040單片機內部PCA可編程計數器陣列產生，并具有結構簡單、信號穩定、實時性強、易擴展的特點。通過硬件實現和系統運行達到了比較理想的控制效果，驗證了系統的可行性。 Abstract: A digital auto-leveling control system based on CAN Bus is introduced.It uses CAN Bus as the method of communication and creates PWM signals by programmable counter array in C8051F040 microcontroller. The system is simple, stable, real-time and expansive.
上傳時間： 2013-10-09
上傳用戶：ligi201200
為了提高環境參數采集的自動化水平，提升效率，設計了無線傳感器系統。本系統運用了傳感器技術、通信技術和單片機技術，實現了對環境溫度、濕度、光照度以及可燃性氣體濃度等參數的檢測。它能夠實時地與上位機進行無線通信，滿足對環境參數實時監測的要求。 Abstract: In order to increase the degree of automation and improve the efficiency of the environment monitoring parameters，the wireless sensor system was developed.Combining with the technique of sensor,automatic monitoring，communication and single-chip microcomputer，it realized real-time monitoring environment parameters,such as temperature，humidity，illumination，concentration of com- bustible gas and so on.At the same time it can communicate with upper personal computers，satisfy the desire of real-time monitoring.
上傳時間： 2013-11-22
上傳用戶：longlong12345678
為解決輸油管道溫度壓力參數實時監測的問題，設計了以C8051F930單片機作為控制核心的超低功耗輸油管道溫度壓力遠程監測系統。現場儀表使用高精度電橋采集數據，通過433 MHz短距離無線通信網絡與遠程終端RTU進行通信，RTU通過GPRS網絡與PC上位機進行遠程數據傳輸，在上位機中實現數據存儲和圖形化界面顯示，從而實現輸油管道溫度壓力參數的實時監測和異常報警。經實驗證明，該系統的12位數據采集精度滿足設計要求，漏碼率小于1%，正常工作時間超過5個月，能實時有效地監測輸油管道的溫度壓力參數，節省大量人工成本，有效預防管道參數異常造成的經濟損失和環境污染。 Abstract: In order to solve the problems on real-time monitoring of pipeline temperature and pressure parameters， the ultra-low power remote pipeline temperature and pressure monitoring system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection， the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU， the GPRS was used by the RTU to transmit data to the PC host computer， and the data was stored and displayed in the PC host computer， so the real-time monitoring and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time， it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
上傳時間： 2013-11-07
上傳用戶：cuibaigao
本文介紹了基于AT89C52 單片機的自動水溫控制系統的設計及實現過程。該系統具有實時顯示、溫度測量、溫度設定并能根據設定值對環境溫度進行調節實現控溫的目的以及達到上下限溫度報警功能，控制算法是基于數字PID 算法。關鍵詞 ：PID AT89C52 脈寬調制 實時 Abstract ： This article describes AT89C52 single-chip microcomputer-basedautomatic water temperature control system design and implementation process. Thesystem has real-time display, temperature measurement, temperature settings and theenvironment in accordance with the temperature settings adjusted to achieve thepurpose of temperature control and reach the upper and lower limits of temperaturealarm function, the control algorithm is based on the digital PID algorithm.Keyword: PID AT89C52 PWM real time
上傳時間： 2013-10-10
上傳用戶：歸海惜雪
NEC 16位MCU參考手冊 The 78K0R/IC3 is a 16-bit single-chip microcontroller that uses a 78K0R CPU core and incorporates peripheral functions, such as ROM/RAM, a multi-function timer, a multi-function serial interface, an A/D converter, a programmable gain amplifier (PGA), a comparator, a real-time counter, and a watchdog timer.
上傳時間： 2013-11-02
上傳用戶：努力努力再努力
基于單DSP的VoIP模擬電話適配器研究與實現:提出和實現了一種新穎的基于單個通用數字信號處理器(DSP)的VoIP模擬電話適配器方案。DSP的I/O和存儲資源非常有限，通常適于運算密集型應用，不適宜控制密集型應用[5]。該系統高效利用單DSP的I/O和片內外存儲器資源，采用μC/OS-II嵌入式實時操作系統，支持SIP和TCP-UDP/IP協議，通過LAN或者寬帶接入，使普通電話機成為Internet終端，實現IP電話。該系統軟硬件結構緊湊高效，運行穩定，成本低，具有廣闊的應用前景。關鍵詞：模擬電話適配器；IP電話；數字信號處理器；μC/OS-II 【Abstract】This paper presents a VoIP ATA solution based on a single digital signal processor (DSP). DSPs are suitable for arithmetic-intensiveapplication and unsuitable for control-intensive application because of the limitation of I/O and memory resources. This solution is based on a 16-bitfixed-point DSP and μC/OS-II embedded real-time operating system. It makes good use of the limited resources, supports SIP and TCP-UDP/IPprotocol. It can connect the analog telephone to Internet and realize the VoIP application. This system has a great future for its high efficiency andlow cost.【Key words】Analog telephone adapter (ATA); Voice over Internet protocol (VoIP); Digital signal processor (DSP); μC/OS-II Research and Implementation of VoIPATA Based on Single DSP
上傳時間： 2013-11-20
上傳用戶：Wwill
This application note shows how to write an Inter Integrated Circuit bus driver (I²C) for the Philips P90CL301micro-controller.It is not only an example of writing a driver, but it also includes a set of application interface software routines toquickly implement a complete I²C multi-master system application.For specific applications the user will have to make minimal changes in the driver program. Using the drivermeans linking modules to your application software and including a header-file into the application sourceprograms. A small example program of how to use the driver is listed.The driver supports i.a. polled or interrupt driven message handling, slave message transfers and multi-mastersystem applications. Furthermore, it is made suitable for use in conjunction with real time operating systems, likepSOS+.
上傳時間： 2013-11-23
上傳用戶：weixiao99
This application note demonstrates how to write an Inter Integrated Circuit bus driver (I2C) for the XA-S3 16-bitMicrocontroller from Philips Semiconductors.Not only the driver software is given. This note also contains a set of (example) interface routines and a smalldemo application program. All together it offers the user a quick start in writing a complete I2C system applicationwith the PXAS3x.The driver routines support interrupt driven single master transfers. Furthermore, the routines are suitable foruse in conjunction with real time operating systems.
上傳時間： 2013-11-02
上傳用戶：zw380105939
在車載自組網中，路由協議很大程度上決定了整個網絡的性能。如何有效的利用車流信息提高傳輸質量是改善路由性能的一個關鍵問題。本文基于速度-密度線性模型，提出了一種實時車流密度的路由協議RVDR（Real-time Vehicle Density Routing）。該協議通過與鄰居節點交換的速度信息，對相關道路車流密度進行預測，并給出基于車流密度信息的路徑選擇方法。仿真結果表明，與現有協議相比，RVDR協議在實時性和高效性等性能方面得到改進。
上傳時間： 2014-07-10
上傳用戶：ZJX5201314
為提升虛擬儀器傳輸速率與實時性能，擴展監測范圍，在VC的軟件平臺上設計了一種全功能虛擬示波器。與傳統虛擬示波器相比，該系統采用嵌入式系統完成信號采集，采用工業以太網為傳輸介質，通過線性插值算法和多線程編程思想，實現波形顯示、參數計算、頻譜分析以及波形存儲及回放功能。實驗結果表明，該虛擬示波器可以實現20 kHz采樣頻率下的波形精確顯示，達到預期的各項指標。 Abstract: o enhance the transfer rate and real-time of virtual instrument performance， expand scope of monitoring， this paper uses the VCs software platform to design a fully functional virtual oscilloscope. Compared with traditional virtual oscilloscope， this system adopts the embedded system to complete the data acquisition， industrial Ethernet as the transmission medium used by the linear interpolation algorithm and multi-threaded programming ideas， namely to achieve waveform display， parameter calculation， spectrum analysis and waveform storage and playback. Experimental results show that the virtual oscilloscope can accurately display the waveform with 20kHz sampling frequency， and achieve the desired targets.
上傳時間： 2013-11-25
上傳用戶：wbwyl
