在理論分析循環(huán)碼編碼和譯碼基本原理的基礎(chǔ)上，提出了基于單片機系統(tǒng)的(24，16)循環(huán)碼軟件實現(xiàn)編碼、譯碼的方案。仿真結(jié)果表明(24，16)循環(huán)碼能有效地克服來自通訊信道的干擾，保證數(shù)據(jù)通信的可靠及系統(tǒng)的穩(wěn)定，使誤碼率大幅度降低。本論文對(24，16)循環(huán)碼的研究結(jié)果表明，可以有效地降低錯誤概率和提高系統(tǒng)的吞吐量，實現(xiàn)糾錯僅需要在接收端增加有限的存儲空間和計算復(fù)雜度，具有一定的實用價值。 Abstract: Based on analyzing the theory of encoding and decoding of cyclic code， this paper showed the schemes of encoding and decoding of(24，16)cyclic code by the software and based on microcontroller. Simulation results show that using (24，16) cyclic codes can effectively overcome the interference from communicATion channel， ensure the reliability and stability of data communicATion systems， and reduce the bit error rate greatly. The results of this paper show that by using the (24，16) cyclic code， the error rate can be reduced and the system throughput can be improved. Meanwhile， the system only needs to enlarge limited storage space and computation the complexity at the receiving end to realize error correction. Thus the (24，16) cyclic code has a practical value.
標簽： 24 16 單片機系統(tǒng) 循環(huán)碼
上傳時間： 2013-11-09
上傳用戶：gaoliangncepu
在航電系統(tǒng)維護過程中，為解決定位故障的效率和降低維修成本等問題，提出了基于ICD（Interface Control Document，接口控制文件）的1553B總線的信息監(jiān)控系統(tǒng)模型。該系統(tǒng)運用數(shù)據(jù)采集卡對總線中傳輸?shù)男盘栍袩o失真、偏差等電氣特性進行檢測，并使用1553B通訊卡通過測控軟件LabWindows/CVI編程與ICD數(shù)據(jù)庫的動態(tài)鏈接，實現(xiàn)總線信息的解析和故障的判斷。與傳統(tǒng)的維護過程相比，這種模型能夠從信號的電氣特性以及信息的解析等全方位的去檢測判斷故障的來源，并且能夠廣泛在其他1553B總線系統(tǒng)內(nèi)擴展應(yīng)用。驗證表明該監(jiān)控系統(tǒng)可以對總線信息進行快速有效地監(jiān)測分析，能滿足應(yīng)用需求。 Abstract: In the process of avionics system maintenance， to solve the problems such as improving the efficiency of fast orientation to troubles and reducing maintenance cost， system of 1553B bus information monitor model based on ICD was proposed. The system observed whether the data which transmitted on the bus appear distortion and deviation by using data acquisition card. And using 1553B communicATion card programming of the measure software LabWindows/CVI and the dynamic linking of ICD database， message analysis and fault estimation could be realized. Compared with traditional maintenance， this model can all-dimensionally detect and analyze the source of faults from both electrical characteristics of the signal and message analysis， and it can be widely applied in the other 1553B system. Experiment shown that this monitor system can effectively detect and analyze the bus message and can meet the application requirements.
標簽： 1553B 總線 信息監(jiān)控
上傳時間： 2013-11-23
上傳用戶：18752787361
為解決當(dāng)前計算機串行通訊接口只有USB，難以滿足舊型號設(shè)備或某些單片機要求RS232通訊的問題，設(shè)計出兩款RS232/USB電路。采用CH341A與MAX223集成電路芯片構(gòu)建標準9線RS232/USB通用接口轉(zhuǎn)換器，無需編程。采用CH341A與PIC16F877A構(gòu)建單片機與計算機之間的USB通訊電路，軟件遵循RS232通訊協(xié)議，硬件進行電平轉(zhuǎn)換。實際使用表明，這兩款產(chǎn)品與計算機端Windows 操作系統(tǒng)下的串口應(yīng)用程序完全兼容，且通訊過程中無握手失敗現(xiàn)象。 Abstract: To solve the problem that current computer serial communicATion only with USB interface can not satisfy with the old type equipments or MCU to communicate with RS232， two kinds of RS232/USB circuit were designed.CH341A and MAX223 integrated circuit chips were used to create a standard 9-line RS232/USB universal interface convertor without programme. CH341A and PIC16F877A chips were adopted to build the USB communicATion circuit between computers and MCU. The software follows RS232 communicATion protocol， and the hardware converts electrical levels. Actual practices indicate that the two manufactures are compatible with serial application program of Windows operation system completely，and get avoid of handshake lost.
上傳時間： 2013-11-03
上傳用戶：siying
摘要 本研究計劃之目的，在整合應(yīng)用以ARM為基礎(chǔ)的嵌入式多媒體實時操作系統(tǒng)于H.264/MPEG-4多媒體上。由于H.264是一種因應(yīng)實時系統(tǒng)(RTOS)所設(shè)計的可擴展性串流傳輸(scalability stream media communicATion)的編碼技術(shù)。H.264主要架構(gòu)于細細粒可擴展(Fine Granula Scalability,FGS)的壓縮編碼機制。細粒度可擴展壓縮編碼技術(shù)是最新MPEG-4串流式傳輸標準，能依頻寛的差異來調(diào)整傳輸?shù)姆绞健＜毩６葦U展縮編碼技術(shù)以編入可選擇性的增強層(enhanced layers)于碼中，來提高影像傳輸?shù)馁|(zhì)量。本計劃主要在于設(shè)計一種簡單有效的實時階層可擴展的影像傳輸系統(tǒng)。在增強層編碼及H.264的基本層(base layer)編碼上使用漸進的細粒度可擴展編碼(Progressive Fine Granularity Scalable,PFGS)能直接使用H.264的格式特色來實現(xiàn)FGS。同時加入了LB-LLF(Layer-Based Least-Laxity-Fir stscheduling algorithm)的排程算法，來增 進網(wǎng)路傳輸影像的質(zhì)量。由實驗結(jié)果顯示本系統(tǒng)在串流影像質(zhì)量PSNR值上確有較佳的效能。
標簽： 芯片系統(tǒng) 架構(gòu) 開發(fā)平臺
上傳時間： 2014-12-26
上傳用戶：mpquest
以C8051F020為核心處理器，設(shè)計無線傳感器網(wǎng)絡(luò)數(shù)據(jù)采集系統(tǒng)。系統(tǒng)采用SZ05-ADV型無線通訊模塊組建Zigbee無線網(wǎng)絡(luò)，結(jié)合嵌入式系統(tǒng)的軟硬件技術(shù)，完成終端節(jié)點的8路傳感器信號的數(shù)據(jù)采集。現(xiàn)場8路信號通過前端處理后，分別送入C8051F020的12位A/D轉(zhuǎn)換器進行轉(zhuǎn)換。經(jīng)過精確處理、存儲后的現(xiàn)場數(shù)據(jù)，通過Zigbee無線網(wǎng)絡(luò)傳送到上位機，系統(tǒng)可達到汽車試驗中無線測試的目的。 Abstract: This paper designs a wireless sensor network system for data acquisition with C8051F020 as core processors.The system used SZ05-ADV wireless communicATion module，set up a Zigbee wireless network， combined with hardware and software technologies of embedded systems，completed the end-node 8-locale sensor signal data acquisition.Eight locale signals were sent separately into the 12-bit ADC of C8051F020 for conversion through front treatment.After accurate processing and storage，the locale data was transmitted to the host computer through Zigbee wireless.The system achieves the purpose of wireless testing in vehicle trial.
標簽： C8051F020 Zigbee 汽車測試 系統(tǒng)設(shè)計
上傳時間： 2013-11-23
上傳用戶：dsgkjgkjg
以太網(wǎng)和CAN總線應(yīng)用廣泛，但由于其通信協(xié)議不同，兩種總線器件間無法進行數(shù)據(jù)通信，因此，設(shè)計了基于CP2200與C8051F040的以太網(wǎng)總線與CAN總線接口轉(zhuǎn)換電路，并給出部分相關(guān)硬件電路與軟件設(shè)計分析。在保證數(shù)據(jù)完整和協(xié)議可靠的前提下，通過握手協(xié)議和簡化的以太網(wǎng)協(xié)議，不僅實現(xiàn)了以太網(wǎng)數(shù)據(jù)與CAN數(shù)據(jù)的轉(zhuǎn)發(fā)，同時還順利的解決了以太網(wǎng)的高速性與CAN的低速率沖突，以及兩者數(shù)據(jù)包之間的大小不同的矛盾。 Abstract: In the development of actual application， Ethernet and CAN bus are used very extensively. Owing to its various communicATion protocols， the communicating between two kinds of bus device can’t be carried out. Therefore， in order to solve this problem， the Ethernet-CAN bus interface circuit based on CP2200 and C8051F040 was designed in this paper， and part of the related hardware circuit and software design analysis were given. On the condition of data’s integrity and protocols’reliability， through the handshaking protocols and the simplified the Ethernet protocol， not only the data switching between CAN and Ethernet was realized， but also the differ in velocity and packet size was solved.
標簽： C8051F040 CAN 以太網(wǎng) 轉(zhuǎn)換
上傳時間： 2013-10-15
上傳用戶：Ants
詳細介紹工控軟件組態(tài)王與單片機多機串口通訊的設(shè)計原理。分析組態(tài)王提供的直接與單片機串口通信方法的優(yōu)點，給出系統(tǒng)基于RS-485總線傳輸?shù)慕涌陔娐吩韴D。根據(jù)組態(tài)王提供的通訊協(xié)議和單片機多機串口通訊的原理，給出程序設(shè)計流程與思路。 Abstract: In this paper，the design principle of communicATion between multi-SCM and KingView by serial ports is described in detail.We analysis the advantage of method supplied by KingView,by which KingView can communicate with serial ports of SCM directly，and provide the system’s interface circuit based on the RS-485transmission line.We provide flow diagram of programming and thinking on the basis of communicATion protocol supplied by KingView and principle of communicATion among multi-SCM through serial ports.
上傳時間： 2013-12-19
上傳用戶：tecman
數(shù)字信號處理器dsPIC33F集多通道高精度A/D轉(zhuǎn)換、多通訊模式、看門狗、CMOS Flash技術(shù)等于一體，其內(nèi)部可完成所有數(shù)據(jù)操作，實現(xiàn)總線不出芯片技術(shù)。將該處理器應(yīng)用于微機保護裝置，提出基于dsPIC33F微處理器的微機保護裝置的設(shè)計方案，給出相應(yīng)的接口電路與軟件流程。該設(shè)計方案結(jié)構(gòu)簡單，性價比及可靠性高，開發(fā)周期短，具有一定的實用推廣價值。所研制的微機保護裝置現(xiàn)場運行效果良好。 Abstract: The dsPIC33F microprocessor has a plentiful interior resource which contains multi-channel，high precision A/D converters，multi-communicATion module，watchdog，CMOS Flash technology，and so on.All data manipulations is accomplished interiorly.What is more，it makes the technology that bus does not go beyond the chip comes into practice.The paper put forwards a design scheme based on dsPIC33F microprocessor.The scheme has the advantages of simple structure，high reliability and shortened exploitation cycle.What is more，it has definite practicality and reference.The microcomputer protection device has been put into operation with excellent effects.
上傳時間： 2013-11-16
上傳用戶：開懷常笑
介紹了當(dāng)前普通標記機控制系統(tǒng)現(xiàn)狀及其存在缺點，給出氣動標記機及相頻修正PWM模式的工作原理。采用ATmega16單片機和USB轉(zhuǎn)換RS232接口器件CH341T實現(xiàn)驅(qū)動控制系統(tǒng)與PC的實時通訊，標記控制系統(tǒng)可升級到USB接口。采用基于ATmega16的相頻修正PWM替換555振蕩電路產(chǎn)生的PWM，可直接通過軟件調(diào)整PWM信號。使用達林頓三極管TIP122替代直流繼電器驅(qū)動高頻電磁閥，使得電磁閥驅(qū)動電路簡單，成本低廉。該控制系統(tǒng)已成功應(yīng)用于氣動標記機。 Abstract: In this paper,the actuality and demerit of the common gas marking machine control systems are described.The operation principle of the gas marking machine and the phase and frequency correct PWM of ATmega16is introduced.The real-time communicATion between the driving control system and PC by CH341T which its function is translated USB to RS232is realized,the control systems is updated grade to USB interface.The PWM signal can be adjustable by software for the555surge circuit was substituted by the phase and frequency.The high frequency electromagnetic value’s driving circuit by DC relay is replaced by TIP122,therefore,the circuit is become simple and the cost cheap.The control systems has been widely used in gas marking machine.
標簽： ATmega 16 標記 控制系統(tǒng)
上傳時間： 2013-10-18
上傳用戶：1427796291
介紹一種簡單射頻識別系統(tǒng)設(shè)計。該設(shè)計包括閱讀器、應(yīng)答器和線圈3部分。由單片機控制閱讀器向應(yīng)答器發(fā)射無線信號，并接收應(yīng)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(yīng)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
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