·詳細說明：雙音多頻的DTMF信號編碼程序，產生DTMF信號進行編碼。- The double sound multi- frequencies DTMF signal coded program, produces the DTMF signal to carry on the code.
上傳時間： 2013-04-24
上傳用戶：yangzhiwei
With more and more multi-frequency clocks being used in today's chips, especially in the communications field, it is often necessary to switch the source of a clock line while the chip is running.
上傳時間： 2013-10-10
上傳用戶：1214209695
This document presents design techniques and reference circuits that power Virtex™-4 FXRocketIO™ multi-gigabit transceivers (MGTs) operating at data rates below 3.125 Gb/s.When using multiple transceivers, it is sometimes preferred to power them from a switchingpower supply. However, switching power supplies generate noise that affects transceiver
上傳時間： 2013-11-18
上傳用戶：huang111
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.
上傳時間： 2013-10-19
上傳用戶：royzhangsz
詳細介紹工控軟件組態王與單片機多機串口通訊的設計原理。分析組態王提供的直接與單片機串口通信方法的優點，給出系統基于RS-485總線傳輸的接口電路原理圖。根據組態王提供的通訊協議和單片機多機串口通訊的原理，給出程序設計流程與思路。 Abstract: In this paper，the design principle of communication between multi-SCM and KingView by serial ports is described in detail.We analysis the advantage of method supplied by KingView,by which KingView can communicate with serial ports of SCM directly，and provide the system’s interface circuit based on the RS-485transmission line.We provide flow diagram of programming and thinking on the basis of communication protocol supplied by KingView and principle of communication among multi-SCM through serial ports.
上傳時間： 2013-12-19
上傳用戶：tecman
數字信號處理器dsPIC33F集多通道高精度A/D轉換、多通訊模式、看門狗、CMOS Flash技術等于一體，其內部可完成所有數據操作，實現總線不出芯片技術。將該處理器應用于微機保護裝置，提出基于dsPIC33F微處理器的微機保護裝置的設計方案，給出相應的接口電路與軟件流程。該設計方案結構簡單，性價比及可靠性高，開發周期短，具有一定的實用推廣價值。所研制的微機保護裝置現場運行效果良好。 Abstract: The dsPIC33F microprocessor has a plentiful interior resource which contains multi-channel，high precision A/D converters，multi-communication module，watchdog，CMOS Flash technology，and so on.All data manipulations is accomplished interiorly.What is more，it makes the technology that bus does not go beyond the chip comes into practice.The paper put forwards a design scheme based on dsPIC33F microprocessor.The scheme has the advantages of simple structure，high reliability and shortened exploitation cycle.What is more，it has definite practicality and reference.The microcomputer protection device has been put into operation with excellent effects.
上傳時間： 2013-11-16
上傳用戶：開懷常笑
以89S52單片機和EP1C6Q240C8型FPGA為控制核心的多功能計數器，是由峰值檢波、A/D轉換、程控放大、比較整形、移相網絡部分組成,可實現測量正弦信號的頻率、周期和相位差的功能。多功能計數器采用等精度的測量方法，可實現頻率為1Hz～10MHz、幅度為0.01～5Vrms的正弦信號的精確測頻，以及頻率為10Hz～100kHz、幅度為0.5～5Vrms的正弦信號精確測相。液晶顯示器能夠實時顯示當前信號的頻率、周期和相位差。該多功能計數器精度高，界面友好，實用性強。 Abstract: A multi-function counter，which uses89S52MCU and EP1C6Q240C8FPGA as a control core，consists of peak detector，A/D conversion，program-controlled amplification，compared shaping and phase-shifting network part.The counter measures the frequency，period and phase of sinusoidal signal.With the equal precision method,the multi-function counter achieves the precise frequency measurement of the sinusoidal signal which its frequency is from1Hz to10MHz，its amplitude is from0.01Vrms to5Vrms，as well as the accurate phase measurement of the sinusoidal signal which its frequency is from10Hz to100kHz，its amplitude is from0.5Vrms to5Vrms.The LCD monitor real-time displays the frequency，period and phase difference of current signal.The multi-function counter features high precision，friendly interface，and strong practical.
上傳時間： 2013-11-15
上傳用戶：gy592333
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.
上傳時間： 2013-11-16
上傳用戶：yare
量測/測試所面臨之問題 此測試驗證上，要使用NI公司之LAB VIEW及DAQ CARD來取代AUDIO PRECISION及其所附軟體ATS。首先需克服硬體解析度上的差異，再來是FFT（FAST FOURIER TRANSFORM,快速傳立業轉換）演算未予的撰寫，這將會影響MULTI-TONE訊號上PEAK值的偵測。另外，以RS-232為I/O介面，并呼叫客戶所提供之DLL檔來與DUT內的IC溝通，但因LAB VIEW無法直接呼叫其STRUCTURE，故需用VC++再編譯一層新的DLL來供LAB VIEW使用。
上傳時間： 2013-12-13
上傳用戶：longlong12345678
針對當前安檢力學試驗機所能完成的試驗種類單一、自動化程度低等問題，提出一種以ATmega128單片機為核心控制器的安檢力學試驗機的設計。詳細闡述了該安檢力學試驗機各個組成部分的設計原理和方案，并且給出了各部分的軟件設計思想和操作流程。經過大量測試試驗表明：設計的安檢力學試驗機可以完成多達十余種的力學安檢試驗，完全符合相關國家標準，并且具有數據采集精度高、傳輸速度快、操作安全簡便等特點，實現了安檢設備的多功能化、數字化和自動化。 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.
上傳時間： 2013-11-05
上傳用戶：a67818601
