为满足矿井安全生产要求，介绍了一种以AT89C51单片机为主控器，对环境空气的温度、有毒易燃气体的浓度等进行检测的监控系统。该系统配合外围电路能实现对上述环境指标的控制并存储相关数据与上位PC机通信。它采用硬件抗干扰和软件抗干扰技术，以确保整个系统工作的准确性。 Abstract: In order to meet the needs of mine produce safety，a kind of intellignet mine ambient monotoring and control system based on AT89C51 is introduced.This system can detect the temperature of ambient of mine，the density of poisonous inflammable gas,combined external circuit.With its function part， this system can change above-mentioned elements.
上传时间： 2013-11-10
上传用户：wendy15
The outputs of the PCA9518 are immediately available as soon as there is a voltage present on thesupply >~1V and behave as described above. The power-on reset of the PCA9518A keeps the outputsturned off during power-up and maintains the high impedance of the outputs throughout the power-upcycle. There is an additional built-in delay after power-up that allows the analog circuits to stabilize beforethe part is activated.
标签： Replacement 9518 NXP PCA
上传时间： 2013-10-26
上传用户：13817753084
The NCV7356 is a physical layer device for a single wire data linkcapable of operating with various Carrier Sense Multiple Accesswith Collision Resolution (CSMA/CR) protocols such as the BoschController Area Network (CAN) version 2.0. This serial data linknetwork is intended for use in applications where high data rate is notrequired and a lower data rate can achieve cost reductions in both thephysical media components and in the microprocessor and/ordedicated logic devices which use the network.The network shall be able to operate in either the normal data ratemode or a high-speed data download mode for assembly line andservice data transfer operations. The high-speed mode is onlyintended to be operational when the bus is attached to an off-boardservice node. This node shall provide temporary bus electrical loadswhich facilitate higher speed operation. Such temporary loads shouldbe removed when not performing download operations.The bit rate for normal communications is typically 33 kbit/s, forhigh-speed transmissions like described above a typical bit rate of83 kbit/s is recommended. The NCV7356 features undervoltagelockout, timeout for faulty blocked input signals, output blankingtime in case of bus ringing and a very low sleep mode current.
上传时间： 2013-10-24
上传用户：s蓝莓汁
Single-Ended and Differential S-Parameters Differential circuits have been important incommunication systems for many years. In the past,differential communication circuits operated at lowfrequencies, where they could be designed andanalyzed using lumped-element models andtechniques. With the frequency of operationincreasing beyond 1GHz, and above 1Gbps fordigital communications, this lumped-elementapproach is no longer valid, because the physicalsize of the circuit approaches the size of awavelength.Distributed models and analysis techniques are nowused instead of lumped-element techniques.Scattering parameters, or S-parameters, have beendeveloped for this purpose [1]. These S-parametersare defined for single-ended networks. S-parameterscan be used to describe differential networks, but astrict definition was not developed until Bockelmanand others addressed this issue [2]. Bockelman’swork also included a study on how to adapt single-ended S-parameters for use with differential circuits[2]. This adaptation, called “mixed-mode S-parameters,” addresses differential and common-mode operation, as well as the conversion betweenthe two modes of operation.This application note will explain the use of single-ended and mixed-mode S-parameters, and the basicconcepts of microwave measurement calibration.
上传时间： 2014-03-25
上传用户：yyyyyyyyyy
Multioutput monolithic regulators are easy to use and fi tinto spaces where multichip solutions cannot. Nevertheless,the popularity of multioutput regulators is temperedby a lack of options for input voltages above 30V andsupport of high output currents. The LT3692A fi lls thisgap with a dual monolithic regulator that operates frominputs up to 36V. It also includes a number of channeloptimization features that allow the LT3692A’s per-channelperformance to rival that of multichip solutions.
上传时间： 2014-01-03
上传用户：Huge_Brother
Source codes and documents for how to find files in phone memory or mmc card in Symbian OS. Compatible for v1.0 above development platform.
标签： documents Compatib Symbian Source
上传时间： 2014-12-07
上传用户：kristycreasy
The flpydisk sample is a floppy driver that resides in the directory \\Ntddk\Src\Storage\Fdc\Flpydsk. It is similar to a class driver in that it sits a level above the floppy disk controller in the driver stack, and brokers communication between the application level and the low-level driver. The floppy driver takes commands from the application and then calls routines in the controller which will in turn perform the actual interaction with the device. The sample compiles in 64-bit, but has not been tested in this environment. It is compatible with x86 and Alpha platforms.
标签： NtddkSrcStorageFdcFlpydsk directory flpydisk resides
上传时间： 2015-03-30
上传用户：龙飞艇
A C++ N-grams Package 2.0 This is a simple C++ n-grams package that includes a header, the corresponding cpp file, and a sample driver program. It is a natural language processing tool for creating n-gram profiles for text documents. The details on usage is documented in the header right above each public function defined. This package is based on Dr. Vlado Keselj s Perl package Text::Ngrams which is available in CPAN.
标签： includes correspo N-grams Package
上传时间： 2015-06-12
上传用户：wfl_yy
This file came from Planet-Source-Code.com...the home millions of lines of source code You can view comments on this code/and or vote on it at: http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=58860&lngWId=1 The author may have retained certain copyrights to this code...please observe their request and the law by reviewing all copyright conditions at the above URL.
标签： Planet-Source-Code millions source lines
上传时间： 2013-12-26
上传用户：dancnc
Person-to-person realtime IP communications, like presence, VoIP and video applications, offer clear benefits for the enterprise as time- and money-savers. Unified functionality is now available, where all of the above are integrated into one streamlined application and interconnect with other networks. This creates a very important business tool and usage is increasing.
标签： Person-to-person communications applications realtime
上传时间： 2015-06-28
上传用户：维子哥哥
