The STWD100 watchdog timer Circuits are self-contained devices which prevent systemfailures that are caused by certain types of hardware errors (non-responding peripherals,bus contention, etc.) or software errors (bad code jump, code stuck in loop, etc.).The STWD100 watchdog timer has an input, WDI, and an output, WDO (see Figure 2). Theinput is used to clear the internal watchdog timer periodically within the specified timeoutperiod, twd (see Section 3: Watchdog timing). While the system is operating correctly, itperiodically toggles the watchdog input, WDI. If the system fails, the watchdog timer is notreset, a system alert is generated and the watchdog output, WDO, is asserted (seeSection 3: Watchdog timing).The STWD100 Circuit also has an enable pin, EN (see Figure 2), which can enable ordisable the watchdog functionality. The EN pin is connected to the internal pull-downresistor. The device is enabled if the EN pin is left floating.
上传时间: 2013-10-22
上传用户:taiyang250072
为了在CDMA系统中更好地应用QDPSK数字调制方式,在分析四相相对移相(QDPSK)信号调制解调原理的基础上,设计了一种QDPSK调制解调电路,它包括串并转换、差分编码、四相载波产生和选相、相干解调、差分译码和并串转换电路。在MAX+PLUSⅡ软件平台上,进行了编译和波形仿真。综合后下载到复杂可编程逻辑器件EPM7128SLC84-15中,测试结果表明,调制电路能正确选相,解调电路输出数据与QDPSK调制输入数据完全一致,达到了预期的设计要求。 Abstract: In order to realize the better application of digital modulation mode QDPSK in the CDMA system, a sort of QDPSK modulation-demodulation Circuit was designed based on the analysis of QDPSK signal modulation-demodulation principles. It included serial/parallel conversion Circuit, differential encoding Circuit, four-phase carrier wave produced and phase chosen Circuit, coherent demodulation Circuit, difference decoding Circuit and parallel/serial conversion Circuit. And it was compiled and simulated on the MAX+PLUSⅡ software platform,and downloaded into the CPLD of EPM7128SLC84-15.The test result shows that the modulation Circuit can exactly choose the phase,and the output data of the demodulator Circuit is the same as the input data of the QDPSK modulate. The Circuit achieves the prospective requirement of the design.
上传时间: 2014-01-13
上传用户:qoovoop
很多不同的厂家生产各种型号的计算机,它们运行完全不同的操作系统,但TCP.IP协议族允许它们互相进行通信。这一点很让人感到吃惊,因为它的作用已远远超出了起初的设想。T C P / I P起源于6 0年代末美国政府资助的一个分组交换网络研究项目,到9 0年代已发展成为计算机之间最常应用的组网形式。它是一个真正的开放系统,因为协议族的定义及其多种实现可以不用花钱或花很少的钱就可以公开地得到。它成为被称作“全球互联网”或“因特网(Internet)”的基础,该广域网(WA N)已包含超过1 0 0万台遍布世界各地的计算机。本章主要对T C P / I P协议族进行概述,其目的是为本书其余章节提供充分的背景知识。 TCP.IP协议 缩略语 ACK (ACKnowledgment) TCP首部中的确认标志 API (Application Programming Interface) 应用编程接口 ARP (Address Resolution Protocol) 地址解析协议 ARPANET(Defense Advanced Research Project Agency NETwork) (美国)国防部远景研究规划局 AS (Autonomous System) 自治系统 ASCII (American Standard Code for Information Interchange) 美国信息交换标准码 ASN.1 (Abstract Syntax Notation One) 抽象语法记法1 BER (Basic Encoding Rule) 基本编码规则 BGP (Border Gateway Protocol) 边界网关协议 BIND (Berkeley Internet Name Domain) 伯克利I n t e r n e t域名 BOOTP (BOOTstrap Protocol) 引导程序协议 BPF (BSD Packet Filter) BSD 分组过滤器 CIDR (Classless InterDomain Routing) 无类型域间选路 CIX (Commercial Internet Exchange) 商业互联网交换 CLNP (ConnectionLess Network Protocol) 无连接网络协议 CRC (Cyclic Redundancy Check) 循环冗余检验 CSLIP (Compressed SLIP) 压缩的S L I P CSMA (Carrier Sense Multiple Access) 载波侦听多路存取 DCE (Data Circuit-terminating Equipment) 数据电路端接设备 DDN (Defense Data Network) 国防数据网 DF (Don’t Fragment) IP首部中的不分片标志 DHCP (Dynamic Host Configuration Protocol) 动态主机配置协议 DLPI (Data Link Provider Interface) 数据链路提供者接口 DNS (Domain Name System) 域名系统 DSAP (Destination Service Access Point) 目的服务访问点 DSLAM (DSL Access Multiplexer) 数字用户线接入复用器 DSSS (Direct Sequence Spread Spectrum) 直接序列扩频 DTS (Distributed Time Service) 分布式时间服务 DVMRP (Distance Vector Multicast Routing Protocol) 距离向量多播选路协议 EBONE (European IP BackbONE) 欧洲I P主干网 EOL (End of Option List) 选项清单结束 EGP (External Gateway Protocol) 外部网关协议 EIA (Electronic Industries Association) 美国电子工业协会 FCS (Frame Check Sequence) 帧检验序列 FDDI (Fiber Distributed Data Interface) 光纤分布式数据接口 FIFO (First In, First Out) 先进先出 FIN (FINish) TCP首部中的结束标志 FQDN (Full Qualified Domain Name) 完全合格的域名 FTP (File Transfer Protocol) 文件传送协议 HDLC (High-level Data Link Control) 高级数据链路控制 HELLO 选路协议 IAB (Internet Architecture Board) Internet体系结构委员会 IANA (Internet Assigned Numbers Authority) Internet号分配机构 ICMP (Internet Control Message Protocol) Internet控制报文协议 IDRP (InterDomain Routing Protocol) 域间选路协议 IEEE (Institute of Electrical and Electronics Engineering) (美国)电气与电子工程师协会 IEN (Internet Experiment Notes) 互联网试验注释 IESG (Internet Engineering Steering Group) Internet工程指导小组 IETF (Internet Engineering Task Force) Internet工程专门小组 IGMP (Internet Group Management Protocol) Internet组管理协议 IGP (Interior Gateway Protocol) 内部网关协议 IMAP (Internet Message Access Protocol) Internet报文存取协议 IP (Internet Protocol) 网际协议 I RTF (Internet Research Task Force) Internet研究专门小组 IS-IS (Intermediate System to Intermediate System Protocol) 中间系统到中间系统协议 ISN (Initial Sequence Number) 初始序号 ISO (International Organization for Standardization) 国际标准化组织 ISOC (Internet SOCiety) Internet协会 LAN (Local Area Network) 局域网 LBX (Low Bandwidth X) 低带宽X LCP (Link Control Protocol) 链路控制协议 LFN (Long Fat Net) 长肥网络 LIFO (Last In, First Out) 后进先出 LLC (Logical Link Control) 逻辑链路控制 LSRR (Loose Source and Record Route) 宽松的源站及记录路由 MBONE (Multicast Backbone On the InterNEt) Internet上的多播主干网 MIB (Management Information Base) 管理信息库 MILNET (MILitary NETwork) 军用网 MIME (Multipurpose Internet Mail Extensions) 通用I n t e r n e t邮件扩充 MSL (Maximum Segment Lifetime) 报文段最大生存时间 MSS (Maximum Segment Size) 最大报文段长度 M TA (Message Transfer Agent) 报文传送代理 MTU (Maximum Transmission Unit) 最大传输单元 NCP (Network Control Protocol) 网络控制协议 NFS (Network File System) 网络文件系统 NIC (Network Information Center) 网络信息中心 NIT (Network Interface Tap) 网络接口栓(S u n公司的一个程序) NNTP (Network News Transfer Protocol) 网络新闻传送协议 NOAO (National Optical Astronomy Observatories) 国家光学天文台 NOP (No Operation) 无操作 NSFNET (National Science Foundation NETwork) 国家科学基金网络 NSI (NASA Science Internet) (美国)国家宇航局I n t e r n e t NTP (Network Time Protocol) 网络时间协议 NVT (Network Virtual Terminal) 网络虚拟终端 OSF (Open Software Foudation) 开放软件基金 OSI (Open Systems Interconnection) 开放系统互连 OSPF (Open Shortest Path First) 开放最短通路优先 PAWS (Protection Against Wrapped Sequence number) 防止回绕的序号 PDU (Protocol Data Unit) 协议数据单元 POSIX (Portable Operating System Interface) 可移植操作系统接口 PPP (Point-to-Point Protocol) 点对点协议 PSH (PuSH) TCP首部中的急迫标志 RARP (Reverse Address Resolution Protocol) 逆地址解析协议 RFC (Request For Comments) Internet的文档,其中的少部分成为标准文档 RIP (Routing Information Protocol) 路由信息协议 RPC (Remote Procedure Call) 远程过程调用 RR (Resource Record) 资源记录 RST (ReSeT) TCP首部中的复位标志 RTO (Retransmission Time Out) 重传超时 RTT (Round-Trip Time) 往返时间 SACK (Selective ACKnowledgment) 有选择的确认 SLIP (Serial Line Internet Protocol) 串行线路I n t e r n e t协议 SMI (Structure of Management Information) 管理信息结构 SMTP (Simple Mail Transfer Protocol) 简单邮件传送协议 SNMP (Simple Network Management Protocol) 简单网络管理协议 SSAP (Source Service Access Point) 源服务访问点 SSRR (Strict Source and Record Route) 严格的源站及记录路由 SWS (Silly Window Syndrome) 糊涂窗口综合症 SYN (SYNchronous) TCP首部中的同步序号标志 TCP (Transmission Control Protocol) 传输控制协议 TFTP (Trivial File Transfer Protocol) 简单文件传送协议 TLI (Transport Layer Interface) 运输层接口 TTL (Ti m e - To-Live) 生存时间或寿命 TUBA (TCP and UDP with Bigger Addresses) 具有更长地址的T C P和U D P Telnet 远程终端协议 UA (User Agent) 用户代理 UDP (User Datagram Protocol) 用户数据报协议 URG (URGent) TCP首部中的紧急指针标志 UTC (Coordinated Universal Time) 协调的统一时间 UUCP (Unix-to-Unix CoPy) Unix到U n i x的复制 WAN (Wide Area Network) 广域网 WWW (World Wide Web) 万维网 XDR (eXternal Data Representation) 外部数据表示 XID (transaction ID) 事务标识符 XTI (X/Open Transport Layer Interface) X/ O p e n运输层接口
上传时间: 2013-11-13
上传用户:tdyoung
机电类比法是一种把机械量通过一定的计算等效类比为电量的方法,其在对电子机械系统的分析中应用非常广泛。它能够把一个较复杂的机械系统类比为我们熟知的电路系统来进行分析,从而使问题的分析得到简化。本文通过对振弦式传感器的分析介绍了机电类比法,并对使用电路进行了相关的分析。 Summary:The electromechanical analogy is assort of analysis which is to analogize the mechanical system by using Circuit system , it applied widely in the filed of analysis the electronic-mechanical system. The analysis can take a complex mechanical system analogous to a Circuitry that we well-known, which can simplify the problems. In the paper, the electro-mechanical analogy method is briefly introduced by analysis the vibrating wire sensor,and have a correlation analysis about the Circuit we used.关键词: 机电类比法 振弦式传感器 频率 振荡 反馈Keyword:electro-mechanical analogy method,vibrating wire sensor,frequency, oscillation, feedback 0 引言振弦式传感器是属于频率式传感器的一种。所谓频率式传感器就是能直接将被测量转换为振动频率信号的传感器,这类传感器一般是通过测量振弦、振筒、振梁、振膜等弹性振体或石英晶体谐振器的固有谐振频率来达到测量引起谐振频率变化的被测非电量的目的,其也称为谐振式传感器[1]。在分析该类传感器中,由于其涉及到频率,就容易让人联想到在电子技术中接触到的RLC振荡电路。因此可以尝试着用类比的方法使之对应起来分析,即机电类比法分析。
上传时间: 2013-11-16
上传用户:paladin
The Maxim Integrated 71M6541-DB REV 3.0 Demo Board is a demonstration board for evaluating the 71M6541 device for single-phase electronic energy metering applications in conjunction with the Remote Sensor Inter-face. It incorporates a 71M6541 integrated Circuit, a 71M6601 Remote Interface IC, peripheral Circuitry such as a serial EEPROM, emulator port, and on-board power supply. A serial to USB converter allows communication to a PC through a USB port. The Demo Board allows the evaluation of the 71M6541 energy meter chip for measurement accuracy and overall system use.
上传时间: 2013-11-06
上传用户:雨出惊人love
Abstract: Communication with 1-Wire slave devices requires a 1-Wire master. There are numerous ways to build a 1-Wire master (see reference design 4206, "Choosing the Right 1-Wire Master for Embedded Applications"). Thisdocument describes the DS1WM, a synthesizable 1-Wire master that can be implemented in an application-specificintegrated Circuit (ASIC) or field-programmable gate array (FPGA).
上传时间: 2014-12-22
上传用户:xanxuan
The CC1101 is a low-cost sub- 1 GHztransceiver designed for very low-powerwireless applications. The Circuit is mainlyintended for the ISM (Industrial, Scientific andMedical) and SRD (Short Range Device)frequency bands at 315, 433, 868, and 915MHz, but can easily be programmed foroperation at other frequencies in the 300-348MHz, 387-464 MHz and 779-928 MHz bands.CC1101 is an improved and code compatibleversion of the CC1100 RF transceiver. Themain improvements on the CC1101 include:
上传时间: 2013-11-12
上传用户:363186
The main objective of this book is to present all the relevant informationrequired for RF and micro-wave power amplifier design includingwell-known and novel theoretical approaches and practical design techniquesas well as to suggest optimum design approaches effectively combininganalytical calculations and computer-aided design. This bookcan also be very useful for lecturing to promote the analytical way ofthinking with practical verification by making a bridge between theoryand practice of RF and microwave engineering. As it often happens, anew result is the well-forgotten old one. Therefore, the demonstrationof not only new results based on new technologies or Circuit schematicsis given, but some sufficiently old ideas or approaches are also introduced,that could be very useful in modern practice or could contributeto appearance of new ideas or schematic techniques.
标签: Amplifier Microwave Design Power
上传时间: 2013-12-22
上传用户:vodssv
Abstract: This application note discusses a design for a phantom antenna power-supply system compatible with theDigital Satellite Equipment Control (DiSEqC) communication standard, using the MAX16948 automotive dual, highvoltageLDO/switch. The presented application Circuit provides a remote antenna power supply and also enables onewaycommunication from the radio head unit to the remote antenna. This system architecture offers flexibility inDiSEqC tone-burst frequency choice (100Hz to 30kHz), enabling users the ability to select the best frequency for theirapplication.
上传时间: 2013-11-17
上传用户:fnhhs
电力设备热点温度与电流在线监测预警系统工作在大型变压器旁,极易受电磁辐射干扰,针对该预警系统的子系统:无线传输部分进行了抗电磁干扰设计,采用Ansoft Designer软件仿真分析了PCB(Printed Circuit Board)中电磁波对PCB电磁兼容性产生的影响,根据其得出的PCB的电流图及近场分布图,分析PCB的电磁兼容性,针对结果中的电磁辐射过高区域进行了重新设计,经Ansoft Designer验证,重新设计后的PCB各项指数有所下降,电磁兼容性得到提高。
上传时间: 2013-11-11
上传用户:ggwz258