實時時鐘是微機保護裝置的重要部件,在討論PCF8583結構與功能的基礎上,提出采用dsPIC33F系列微處理器與串行I2C時鐘PCF8583的接口設計方案,給出了相應的接口電路與軟件流程。該設計方案結構簡單,可靠性高,開發周期短,具有一定的實用與參考價值。所設計的微機保護裝置已投入現場運行,效果良好。 Abstract: Real-time clock chip is an important part in microcomputer protection device.Based on discussing the structure and function of PCF8583,a new interface scheme which uses dsPIC33F microprocessor and serial clock chip(I2C)PCF8583is proposed.The method of the circuit design and the main software flow are introduced in this paper.The scheme has simple structure,higher reliability and shorter exploitation cycle,so has definite practicality or reference value.The microcomputer protection device has been put into operation with better effects.
上傳時間: 2013-11-18
上傳用戶:Thuan
詳細介紹了PCI9052接口器件的功能、結構和使用方法,并結合實際給出了基于PCI9052器件開發PCI總線接口卡的應用實例。 Abstract: The main functions,structures and usage of PCI9052inferface chip are introduced in detail in this paper.And an application example of designing PCI bus interface card based on PCI9052is proposed in this paper.
上傳時間: 2013-10-16
上傳用戶:togetsomething
針對51單片機系統中常用的A/D轉換器價格高、精度低的缺點,介紹TI公司的16 位的帶有I2C串行接口的A/D轉換器ADS1110的工作原理,給出ADS1110與AT89C51單片機系統的接口電路和軟件設計。實踐證明,ADS1110具有高性價比和實用性。 Abstract: According to the disadvantages of high expense and low accuracy of the general A/D converter used in MCS51 microchip system,the principle and working process of a high accuracy 16-bit A/D conversion ADS1110 which has I2C bus and belongs to TI Company are proposed here as well as the interface of ADS1110 to AT89C51 and software list.It is proved to be high performance index and practicability.
上傳時間: 2013-11-21
上傳用戶:gyq
將現行的供暖計費方式由按建筑面積計費變為按消耗的熱能計費是供暖計費方式發展趨勢,為了滿足這一計費方式變化的需要,設計了基于IC卡的預付費式新型供暖計費系統,通過測量用戶采暖系統進出口的溫度和流量,計算用戶消耗的熱能,利用IC卡記錄用戶預付費的金額和當年熱能的單價,根據熱能消耗和當年熱能的單價計算用戶采暖費,根據實際發生的供暖費用和預付費金額控制供暖的開停,這一計費方式的變化使供暖計費更趨合理。 Abstract: It is trend that the mode of heat charging is changed from billing by building area to by thermal energy. In order to meet the needs of heat charging mode changing, a new system of heat charging based on IC card is proposed. The user?蒺s energy consumption is calculated by measuring the user inlet and outlet temperature and flow,using the IC card to record the prepaid amount and the current price of heat. The user?蒺s heating costs is calculated according to energy consumption and current price, according to actual heating costs and prepaid amount,the system controls the heating opening or stopping. It is more reasonable that calculated heating costs by user heat consumption
上傳時間: 2013-10-14
上傳用戶:大融融rr
針對無位置傳感器無刷直流電機的位置檢測問題,本文應用單片機成功地實現了一種軟件檢測方法,并給出了實測波形加以驗證。關鍵詞: 無刷直流電機 無傳感器 位置檢測Abstract: As to the position-detecting problem of sensorless brushless DC motor, a softwarerealization by microcomputer is proposed successfully in the paper. Experiment results are also presented to verify the method.Keywords: brushless DC motor, sensorless, position detecting
上傳時間: 2013-11-01
上傳用戶:aappkkee
針對嵌入式機器視覺系統向獨立化、智能化發展的要求,介紹了一種嵌入式視覺系統--智能相機。基于對智能相機體系結構、組成模塊和圖像采集、傳輸和處理技術的分析,對國內外的幾款智能相機進行比較。綜合技術發展現狀,提出基于FPGA+DSP模式的硬件平臺,并提出智能相機的發展方向。分析結果表明,該系統設計可以實現脫離PC運行,完成圖像獲取與分析,并作出相應輸出。 Abstract: This paper introduced an embedded vision system-intelligent camera ,which was for embedded machine vision systems to an independent and intelligent development requirements. Intelligent camera architecture, component modules and image acquisition, transmission and processing technology were analyzed. After comparing integrated technology development of several intelligent cameras at home and abroad, the paper proposed the hardware platform based on FPGA+DSP models and made clear direction of development of intelligent cameras. On the analysis of the design, the results indicate that the system can run from the PC independently to complete the image acquisition and analysis and give a corresponding output.
上傳時間: 2013-10-24
上傳用戶:bvdragon
在研究傳統家用燃氣報警器的基礎上,以ZigBee協議為平臺,構建mesh網狀網絡實現網絡化的智能語音報警系統。由于傳感器本身的溫度和實際環境溫度的影響,傳感器標定后采用軟件補償方法。為了減少系統費用,前端節點采用半功能節點設備,路由器和協調器采用全功能節點設備,構建mesh網絡所形成的家庭內部報警系統,通過通用的電話接口連接到外部的公用電話網絡,啟動語音模塊進行報警。實驗結果表明,在2.4 GHz頻率下傳輸,有墻等障礙物的情況下,節點的傳輸距離大約為35 m,能夠滿足家庭需要,且系統工作穩定,但在功耗方面仍需進一步改善。 Abstract: On the basis of studying traditional household gas alarm system, this paper proposed the platform for the ZigBee protocol,and constructed mesh network to achieve network-based intelligent voice alarm system. Because of the sensor temperature and the actual environment temperature, this system design used software compensation after calibrating sensor. In order to reduce system cost, semi-functional node devices were used as front-end node, however, full-function devices were used as routers and coordinator,constructed alarm system within the family by building mesh network,connected to the external public telephone network through the common telephone interface, started the voice alarm module. The results indicate that nodes transmit about 35m in the distance in case of walls and other obstacles by 2.4GHz frequency transmission, this is able to meet family needs and work steadily, but still needs further improvement in power consumption.
上傳時間: 2013-10-30
上傳用戶:swaylong
為滿足無線網絡技術具有低功耗、節點體積小、網絡容量大、網絡傳輸可靠等技術要求,設計了一種以MSP430單片機和CC2420射頻收發器組成的無線傳感節點。通過分析其節點組成,提出了ZigBee技術中的幾種網絡拓撲形式,并研究了ZigBee路由算法。針對不同的傳輸要求形式選用不同的網絡拓撲形式可以盡大可能地減少系統成本。同時針對不同網絡選用正確的ZigBee路由算法有效地減少了網絡能量消耗,提高了系統的可靠性。應用試驗表明,采用ZigBee方式通信可以提高傳輸速率且覆蓋范圍大,與傳統的有線通信方式相比可以節約40%左右的成本。 Abstract: To improve the proposed technical requirements such as low-ower, small nodes, large capacity and reliable network transmission, wireless sensor nodes based on MSP430 MCU and CC2420 RF transceiver were designed. This paper provided network topology of ZigBee technology by analysing the component of the nodes and researched ZigBee routing algorithm. Aiming at different requirements of transmission mode to choose the different network topologies form can most likely reduce the system cost. And aiming at different network to choose the correct ZigBee routing algorithm can effectively reduced the network energy consumption and improved the reliability of the system. Results show that the communication which used ZigBee mode can improve the transmission rate, cover more area and reduce 40% cost compared with traditional wired communications mode.
上傳時間: 2013-10-09
上傳用戶:robter
同步技術是跳頻通信系統的關鍵技術之一,尤其是在快速跳頻通信系統中,常規跳頻通信通過同步字頭攜帶相關碼的方法來實現同步,但對于快跳頻來說,由于是一跳或者多跳傳輸一個調制符號,難以攜帶相關碼。對此引入雙跳頻圖案方法,提出了一種適用于快速跳頻通信系統的同步方案。采用短碼攜帶同步信息,克服了快速跳頻難以攜帶相關碼的困難。分析了同步性能,仿真結果表明該方案同步時間短、虛警概率低、捕獲概率高,同步性能可靠。 Abstract: Synchronization is one of the key techniques to frequency-hopping communication system, especially in the fast frequency hopping communication system. In conventional frequency hopping communication systems, synchronization can be achieved by synchronization-head which can be used to carry the synchronization information, but for the fast frequency hopping, Because modulation symbol is transmitted by per hop or multi-hop, it is difficult to carry the correlation code. For the limitation of fast frequency hopping in carrying correlation code, a fast frequency-hopping synchronization scheme with two hopping patterns is proposed. The synchronization information is carried by short code, which overcomes the difficulty of correlation code transmission in fast frequency-hopping. The performance of the scheme is analyzed, and simulation results show that the scheme has the advantages of shorter synchronization time, lower probability of false alarm, higher probability of capture and more reliable of synchronization.
上傳時間: 2013-11-23
上傳用戶:mpquest
提出了一種以ARM微處理器為控制核心的遠程無線視頻監控終端的設計方案,其監控終端的硬件設計包括視頻采集處理、中央管理控制、無線傳輸3個模塊。并給出了監控終端的軟件開發平臺和開發模式的系統啟動代碼、嵌入式Linux系統移植以及驅動程序和應用程序。測試結果表明,該監控終端設計方案合理、有效,基本滿足監控需求。 Abstract: A remote wireless video monitoring terminal design, which uses ARM microprocessor as its core control, is proposed in this paper.The hardware design of monitoring terminal system is composed of the video acquisition and processing module, the central management and control module, wireless transmission module.Meanwhile the monitoring terminal-s software development platform and development patterns are designed. Also the design of the system-s start codes, embedded Linux system-s transplantation process, driver and the corresponding applications are given. The results showed that the monitoring terminal design is reasonable, effective, basically meet monitoring requirements.
上傳時間: 2013-11-13
上傳用戶:wanqunsheng