写给想当程序员的朋友 开发者最好的初学思想 -To those who want to become programmers\r\r\nThe best thinking for new develo
标签： 程序员
上传时间： 2013-05-30
上传用户：ccclll
Abstract: Investment in smart meters and smart grid end equipment continues to grow worldwide as countriestry to make their electric delivery systems more efficient. However, as critical as the electric deliveryinfrastructure is, it is normally not secured and thus subject to attack. This article describes the concept oflife-cycle security—the idea that embedded equipment in the smart grid must have security designed into theentire life of the product, even back to the contract manufacturer. We also talk about how life-cycle securityapplies to embedded equipment in the smart grid. Potential threats are discussed, as are potential solutionsto mitigate the risks posed by those threats.
上传时间： 2014-12-24
上传用户：熊少锋
Abstract: This article discusses the requirements and design considerations for automotive applications, including those for enginecontrol, infotainment, and body electronics. It also discusses several Maxim devices that are ideal for automotive applications.
上传时间： 2013-10-27
上传用户：jiangxiansheng
For a variety of reasons, it is desirable to charge batteriesas rapidly as possible. At the same time, overchargingmust be limited to prolong battery life. Such limitation ofovercharging depends on factors such as the choice ofcharge termination technique and the use of multi-rate/multi-stage charging schemes. The majority of batterycharger ICs available today lock the user into one fixedcharging regimen, with at best a limited number ofcustomization options to suit a variety of application needsor battery types. The LTC®1325 addresses these shortcomingsby providing the user with all the functionalblocks needed to implement a simple but highly flexiblebattery charger (see Figure 1) which not only addressesthe issue of charging batteries but also those of batteryconditioning and capacity monitoring.
上传时间： 2013-10-19
上传用户：royzhangsz
When a system designer specifies a nonisolated dc/dc powermodule, considering the needed input voltage range isequally as important as considering the required performanceattributes and features. Generally, nonisolated moduleshave either a narrow or a wide input voltage range. Narrowinputmodules typically have a nominal input voltage of3.3, 5, or 12 V. For systems that operate from a tightlyregulated input bus—such as those that do not use batterybackup—a narrow-input module is often adequate sincethe input remains fairly stable.Offering greater flexibility, wide-input modules operatewithin a range of 7 to 36 V, which includes the popular12- or 24-V industrial bus. This enables a single module tobe used for generating multiple voltages. These modulesare ideal for industrial controls, HVAC systems, vehicles,medical instrumentation, and other applications that usea loosely regulated distribution bus. In addition, systemspowered by a rectifier/battery charger with lead-acidbattery backup almost always require wide-input modules.System designers who choose power supplies may wantto take a close look at the latest generation of wide-inputdc/dc modules.
标签： Wide-input modules offer dc
上传时间： 2014-12-24
上传用户：dragonhaixm
针对当前安检力学试验机所能完成的试验种类单一、自动化程度低等问题，提出一种以ATmega128单片机为核心控制器的安检力学试验机的设计。详细阐述了该安检力学试验机各个组成部分的设计原理和方案，并且给出了各部分的软件设计思想和操作流程。经过大量测试试验表明：设计的安检力学试验机可以完成多达十余种的力学安检试验，完全符合相关国家标准，并且具有数据采集精度高、传输速度快、操作安全简便等特点，实现了安检设备的多功能化、数字化和自动化。 Abstract: Currently， many mechanical security testing machines have only one function. The degree of automation of them is low. To solve those problems， a new kind of mechanical security testing machine， using ATmega128 micro-controller as its core controller， has been advanced. It describes the components of the machine. The principles and the scheme in the designing processes are presented in detail， and the software architecture and the operation processes of each part are given. After having done many testing， we have reached the following conclusions: the mechanical security testing machine presented can do over ten mechanical security tests complying with related national standards. It has high data acquisition accuracy and high transmission speed. The operation of the machine is simple and safe. In general， this machine is a multi-functional， highly automatic， digitalized security testing device.
上传时间： 2013-11-05
上传用户：a67818601
Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their productsor to discontinue any product or service without notice, and advise customers to obtain the latestversion of relevant information to verify, before placing orders, that information being relied onis current and complete. All products are sold subject to the terms and conditions of sale suppliedat the time of order acknowledgement, including those pertaining to warranty, patentinfringement, and limitation of liability.
标签： Assembly Language C6000 320C
上传时间： 2013-11-12
上传用户：chens000
The C500 microcontroller family usually provides only one on-chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.
标签： synchronous Emulating serial
上传时间： 2014-01-31
上传用户：z1191176801
In this document, the term Ô60xÕ is used to denote a 32-bit microprocessor from the PowerPC architecture family that conforms to the bus interface of the PowerPC 601ª, PowerPC 603ª, or PowerPC 604 microprocessors. Note that this does not include the PowerPC 602ª microprocessor which has a multiplexed address/data bus. 60x processors implement the PowerPC architecture as it is speciÞed for 32-bit addressing, which provides 32-bit effective (logical) addresses, integer data types of 8, 16, and 32 bits,and ßoating-point data types of 32 and 64 bits (single-precision and double-precision).1.1 Overview The MPC106 provides an integrated high-bandwidth, high-performance, TTL-compatible interface between a 60x processor, a secondary (L2) cache or additional (up to four total) 60x processors, the PCI bus,and main memory. This section provides a block diagram showing the major functional units of the 106 and describes brießy how those units interact.Figure 1 shows the major functional units within the 106. Note that this is a conceptual block diagram intended to show the basic features rather than an attempt to show how these features are physically implemented on the device.
上传时间： 2013-10-08
上传用户：18711024007
MPC7400 Part Number SpeciÞcationThis document describes part number speciÞc changes to recommended operating conditions and revised electrical speciÞcations,as applicable, from those described in the generalMPC7400 Hardware SpeciÞcations.SpeciÞcations provided in this Part Number SpeciÞcation supersede those in theMPC7400 Hardware SpeciÞcationsdated 9/99(order #: MPC7400EC/D) for these part numbers only; speciÞcations not addressed herein are unchanged. This document isfrequently updated, refer to the website at http://www.mot.com/SPS/PowerPC/ for the latest version.Note that headings and table numbers in this data sheet are not consecutively numbered. They are intended to correspond to theheading or table affected in the general hardware speciÞcation.
上传时间： 2014-12-28
上传用户：huyahui
