The ability to write efficient, high-speed arithmetic routines ultimately depends upon your knowledge of the elements of arithmetic as they exist on a computer. That conclusion and this book are the result of a long and frustrating search for information on writing arithmetic routines for real-time embedded systems. With instruction cycle times coming down and clock rates going up, it would seem that speed is not a problem in writing fast routines. In addition, math coprocessors are becoming more popular and less expensive than ever before and are readily available. These factors make arithmetic easier and faster to use and implement. However, for many of you the systems that you are working on do not include the latest chips or the faster processors. Some of the most widely used microcontrollers used today are not Digital Signal Processors (DSP), but simple eight-bit controllers such as the Intel 8051 or 8048 microprocessors.
标签： arithmetic high-speed ultimately efficient
上传时间： 2014-11-30
上传用户：lizhen9880
Performance Comparison of Two On-Demand Routing Protocols depends on Traffic Density by Using UWB-IR as Pyhisical and MAC Layer at Outdoor Peer to Peer Sensor Network
标签： Performance Comparison On-Demand Protocols
上传时间： 2017-05-28
上传用户：三人用菜
A light-emitting diode (LED) is a semiconductor device that emits narrow-spectrum incoherent light when forward-biased.The color of the emitted light depends on the chemical composition of the semiconductor material used, and can benear-ultraviolet, visible or infrared. LEDs are more prevalent today than ever before, replacing traditional incandescent andfluorescent bulbs in many lighting applications. Incandescents use a heated filament, are subject to breakage and burnoutand operate at a luminous efficiency of 2% to 4%. Fluorescents are more efficient, at 7% to 12%, but require highdrive voltage and contain mercury, a toxic substance that may be eventually banned in certain countries. LEDs, however,produce light directly through electroluminescence, operate at low voltage and can deliver over 20% luminous efficiency.
上传时间： 2013-11-07
上传用户：xiaoyuer
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
The data plane of the reference design consists of a configurable multi-channel XBERT modulethat generates and checks high-speed serial data transmitted and received by the MGTs. Eachchannel in the XBERT module consists of two MGTs (MGTA and MGTB), which physicallyoccupy one MGT tile in the Virtex-4 FPGA. Each MGT has its own pattern checker, but bothMGTs in a channel share the same pattern generator. Each channel can load a differentpattern. The MGT serial rate depends on the reference clock frequency and the internal PMAdivider settings. The reference design can be scaled anywhere from one channel (two MGTs)to twelve channels (twenty-four MGTs).
上传时间： 2013-12-25
上传用户：jkhjkh1982
The ICA/BSS algorithms are pure mathematical formulas, powerful, but rather mechanical procedures: There is not very much left for the user to do after the machinery has been optimally implemented. The successful and efficient use of the ICALAB strongly depends on a priori knowledge, common sense and appropriate use of the preprocessing and postprocessing tools. In other words, it is preprocessing of data and postprocessing of models where expertise is truly ne
标签： mathematical algorithms mechanical procedures
上传时间： 2015-03-31
上传用户：silenthink
动态链接库程序的编写。静态库与动态库的区别，以及调用程序在链接静态库和动态库时的区别。如何利用工具查看动态链接库输出的函数，depends工具的使用，C++编译器名字改编技术对动态链接库输出函数的影响，extern "C"的用法，利用模块定义文件来解决C++名字改编的问题。用typedef定义指向函数的指针类型，如何获得动态连接库里的函数的指针。
上传时间： 2014-01-19
上传用户：llandlu
动态链接库程序的编写,如何利用工具查看动态链接库输出的函数，depends工具的使用
上传时间： 2015-07-09
上传用户：清风冷雨
动态链接库程序的编写。静态库与动态库的区别，以及调用程序在链接静态库和动态库时的区别。如何利用工具查看动态链接库输出的函数，depends工具的使用，C++编译器名字改编技术对动态链接库输出函数的影响，extern "C"的用法，利用模块定义文件来解决C++名字改编的问题。用typedef定义指向函数的指针类型，如何获得动态连接库里的函数的指针。
上传时间： 2016-04-30
上传用户：wuyuying
This standard describes a keyed-hash message authentication code (HMAC), a mechanism for message authentication using cryptographic hash functions. HMAC can be used with any iterative Approved cryptographic hash function, in combination with a shared secret key. The cryptographic strength of HMAC depends on the properties of the underlying hash function. The HMAC specification in this standard is a generalization of Internet RFC 2104, HMAC, Keyed-Hashing for Message Authentication, and ANSI X9.71, Keyed Hash Message Authentication Code.
标签： message authentication keyed-hash describes
上传时间： 2014-01-07
上传用户：凤临西北
