Abstract: Alexander Graham Bell patented twisted pair wires in 1881. We still use them today because they work so well. In addition we have the advantage ofincredible computer power within our world. Circuit simulators and filter design programs are available for little or no cost. We combine the twisted pair and lowpassfilters to produce spectacular rejection of radio frequency INTERFERENCE (RFI) and electromagnetic INTERFERENCE (EMI). We also illustrate use of a precision resistorarray to produce a customizable differential amplifier. The precision resistors set the gain and common mode rejection ratios, while we choose the frequencyresponse.
Abstract: Class D amplifiers are typically very efficient, making them ideal candidates for portable applications that require longbattery life and low thermal dissipation. However, electromagnetic INTERFERENCE (EMI) is an issue that commonly accompanies theClass D switching topology. Active-emissions limiting reduces radiated emissions and enables "filterless" operation, allowingdesigners to create small, efficient portable applications with low EMI.
設計了水聲信號發(fā)生系統(tǒng)中的功率放大電路，可將前級電路產生的方波信號轉換為正弦信號，同時進行濾波、功率放大，使其滿足換能器對輸入信號的要求。該電路以單片機AT89C52，集成6階巴特沃思低通濾波芯片MF6以及大功率運算放大器LM12為核心，通過標準RS232接口與PC進行通信，實現信號增益的程控調節(jié)，對干擾信號具有良好的抑制作用。經調試該電路工作穩(wěn)定正常，輸出波形無失真，在輸出功率以及放大增益、波紋系數等方面均滿足設計要求。
This paper presented a design and implementation of underwater acoustic power amplifer. This circuit converted the rectangle signal generated by frontend circuit into the sine signal， then filtered and power amplification， it meets the requirements of the transducer.Included AT89C52， 6th order Butterworth filter MF6， hipower amplififier LM12.Communication with PC through the RS232 port. The signal gain is adjustable and could be remote controlled. It has a good inhibitory effect on the INTERFERENCE signal. After debugged， this circuit works stable， the output waveform has no distortion， it meets the design requirement in outprt power， amplifier gain and ripple factor.
在理論分析循環(huán)碼編碼和譯碼基本原理的基礎上，提出了基于單片機系統(tǒng)的(24，16)循環(huán)碼軟件實現編碼、譯碼的方案。仿真結果表明(24，16)循環(huán)碼能有效地克服來自通訊信道的干擾，保證數據通信的可靠及系統(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，實現糾錯僅需要在接收端增加有限的存儲空間和計算復雜度，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.
針對盤山路存在的轉彎盲區(qū)，即在轉彎時司機無法得知彎路對面是否有車輛通過，設計一種基于C8051F310的山路轉彎預防警示系統(tǒng)。該系統(tǒng)利用一階濾波算法檢測山路轉彎時是否有車輛通過。運用該算法可增強系統(tǒng)檢測的實時性，提高檢測機動車輛的靈敏度，同時大大減少環(huán)境溫度對檢測的干擾。試驗表明該系統(tǒng)能夠正確指示出在山路轉彎時是否有車輛通過，目前該系統(tǒng)已安裝在盤山路上，可大大減少事故的發(fā)生率。
Abstract:
Aiming at passing hilly road，there is a turn blind spot.Motormen usually do not know if the passing of vehicles pass the road.So a system of defending accident on hilly road is designed,which is based on MCU C8051F310.The sys-tem uses the first-order filter algorithm to detect whether there are passing vehicles.This algorithm enhances the real-time detection and improves the sensitivity of detection vehicles.Meanwhile,it reduces the detection INTERFERENCE of environmen-tal temperature.The experimental results show that this system can exactly indicate if there are passing vehicles.At present,the system has been successfully applied to hilly road.The system can greatly decrease accident.
介紹了一種基于C8051F020單片機的多路壓力測量儀。該測量儀選用電阻應變式壓力傳感器采集壓力信號，并經放大電路處理后送入C8051F020單片機，再由C8051F020單片機內部的A/D轉換器將采集到的壓力信號進行模數轉化，然后分別對數據進行存儲和顯示。該測量儀能測量6路壓力信號，并且各測量點都能單獨檢測和設置。由于采用了C8051F020單片機，簡化了硬件電路，增強了抗干擾能力，使得測量儀具有測量精度高，沖擊小等特點。
Abstract:
A measurement apparatus for multi-channel pressure based on single chip microcomputer is introduced.It can measure 6 channels signal of the pressure，and the pressure measure points can be detection and located individually.The pressure signal sampling is obtained by resistor stress-type pressure sensors，the digital signals of 6 channels are collected through amplifying and adjustment circuit of pressure signals and internal integrated A/D converter of MCU.Finally，and it realizes the function to store and display data separately.C8051F020 was used to made hardware circuit simple，and it also enhanced the anti-INTERFERENCE ability.It features high precision and little impact.
一種基于ST62單片機的稱重顯示控制器A Weighing Display Controller Based on ST62 Single Chip Computer祛 FA(上海時博飛奧控制系統(tǒng)有限公司，上海201100)摘要在介紹了基于ST62單片機的基礎上，詳細描述了稱重顯控制器的硬件設計和軟件設計思路。該控制器結構簡單、操作方便、抗擾能力強等優(yōu)點;具有較好的推廣應用價值。關鍵詞稱重顯示控制儀ST62單片機硬件設計軟件設計Abstract Ont heb asiso fin torductiono fST 62s inglec hipc omputer,th ed esignc oncrptof h ardwarea nds oftwarefo rw eighingd isplayc ontorleris d escrbed.The controler features simple structure, ease operation, powerful capability of anti-INTERFERENCE, etc.，it is wealth to be promoted into practicalapplicationsKeywords We妙噸display0 引言ST62s inglec hip Hardwared esign Softwaer design備 份 振 蕩器，振蕩器保護電路，上電復位及低壓檢測復稱 重 顯 示控制器是一種具有數字顯示、開關量輸出、定值控制和通信功能的以微機為操作核心的稱重控制裝置。它是電子衡器的重要基礎部件，直接影響電子衡器及電子稱重系統(tǒng)的功能和性能。與合適的傳感器及承重傳力復位系統(tǒng)組合可組成配料秤、料斗秤、定值秤、平臺秤、汽車秤等，廣泛應用于電力、化工、建筑、冶金、交通運輸、食品、軍工等部門，是進行自動稱重配料控制和生產過程自動化必不可少的重要檢測、控制裝置。隨著 稱 重 計量自動化水平的提高，對稱重顯示控制器的要求也越來越高。為實現低漂移、高穩(wěn)定，本控制器采用低漂移、高增益放大器AD620和高分辨率的A/D轉換器CS5550。為提高穩(wěn)定性和可靠性，采用集成度高的、抗干擾能力強的ST62單片機。
單片機系統(tǒng)“PC”失控的軟件措施Software Measure of GettingO uto fC ontrolfo r“PC"in S ingleC hipC omputerS ystem謐 加 春 王 曉 基 雷 小 華(江 西 理 工 大 學機 電 工 程 學 院 ，贛 州 34 10 00)摘要單片機系統(tǒng)在實際工業(yè)現場中可能遇到各種干擾和自身的隨機性故障。現場惡劣的環(huán)境有可能使計算機系統(tǒng)發(fā)生異常，計算機程序指針“PC”失控就是常見的故障之一，如果發(fā)生“PC”失控，將導致CPI工作混亂，釀成嚴重的事故。研究了“PC”失控的原因，并指出軟件抗干擾的幾種方法，有效保證單片機系統(tǒng)的正常工作。關鍵詞單片機“PC”失控抗干擾Abstract Inp racticalin dustrialfi elds,th ereis v ariousin terferencea fectingo perationo fsi nglec hipc omputersy stemsa ndt hec omputersy stems。fac噸random faults飾themselves. It is very common that the severe environment makes the computer systems abnormal. The program counter "PC"gettingo utof co ntorlis on eo fth ec ommonfa ults.If th isoc curs,C PUw ouldb eru nningo utof or deran din torducesse riousan cient.T hec ausesof " PC"geting out of control， studied in this paper and some countermeasures of anti-INTERFERENCE師software are given to ensure single chip computer systemworking properly.Keywords Single。飾computer Porgramc ounter"P C" Anti-interfeernc
在設 計 和 開發(fā)單片機系統(tǒng)時，一般難以周全地預計單片機系統(tǒng)在實際工業(yè)現場中可能遇到的各種干擾和自身的隨機性故障。因此，除了采取防止和抑制干擾的各項措施外，還應該借助于軟件措施克服某些干擾，系統(tǒng)還應具備迅速自行恢復的能力。本文介紹的應對單片機系統(tǒng)PC失控的軟件措施，設計靈活，節(jié)省硬件資源，能保證測控系統(tǒng)長期可靠地運行。MC S- 5 1單片機以其優(yōu)良的性能價格比大量應用于工業(yè)現場測試和控制領域。但是，現場惡劣的環(huán)境有可能使計算機系統(tǒng)發(fā)生異常，計算機程序指針PC失控就是常見的故障之一，一旦發(fā)生PC“走飛”，計算機系統(tǒng)就會出現工作混亂，釀成嚴重的事故。為 了 在 CP 失控時盡量減少由此帶來的不利影響，并盡快使系統(tǒng)恢復正常，需要采取一定的軟件措施和硬件措施。常見的硬件措施有“看門狗”電路。軟件措施設置的前提條件是:①在干擾作用下，微機系統(tǒng)硬件部分不會受到任何損壞，或者損壞部分設置有監(jiān)測狀態(tài)可供查詢;②程序區(qū)不會受到干擾侵害。單片機系統(tǒng)的程序和表格以及重要的參數均設置在ROM區(qū)，不會因干擾的侵人而改變;③ RAM區(qū)中的重要數據不會被破壞，或者雖然被破壞，但是可以重新建立。
Abstract: Engineers often wish that radio susceptibility (RS) or radio immunity could be cured with an antibiotic, a vaccine, or someform of cure-all. Unfortunately, solving the RS problem is not that easy. Indeed, the laws of physics apply. In this article we discusssources of RS. We also offer tips and hints to protect systems, power supplies, printed circuit boards (PCBs), and electroniccomponents from radio frequency INTERFERENCE.
