本系统分电压测量和信号产生输出两大部分，电压测量部分以模拟电路为主，配合放大模块、A/D转化模块、显示模块；通过凌阳单片机进行数据处理，在误差允许范围内显示测量电压值。信号产生以直接数字式频率合成器(Direct Digital Frequency Synthesis,简称DDS或DDFS)为核心，经过AT89S52对DDS芯片内部进行控制，使之输出标准正弦波形，利用编程实现频率预置、步进，达到电压输出频率的可调节步进。通过调试与测量完成了题目的基本部分和全部发挥部分的要求并有自己的创新
上传时间： 2017-08-08
上传用户：comua
While faster processors, larger memory, and powerful graphics are fundamental requirements for workstations, users are also demanding a low-cost, solution-based approach wrapped around a standards-based technology. The Sun UltraTM 20 Workstation, which leverages the AMD OpteronTM processor with Direct Connect Architecture based on AMD64 technology, provides multiple operating system choices and leading nVidia graphics, delivers a platform that offers flexibility and performance in a cost-effective package with solutions to benefit customers across the board.
标签： requirements fundamental processors graphics
上传时间： 2017-08-17
上传用户：zhaiye
AVR single-chip developed by a very low threshold, as long as the computer will be able to study the development of AVR microcontroller. Only a single-chip ISP download beginners line, the editing, debugging of software programs through a direct line into the AVR microcontroller, which can develop AVR Series Single-chip package of a variety of devices. AVR single-chip microcomputer in the industry known as "front-line struggle to seize state power."
标签： single-chip developed threshold the
上传时间： 2017-09-12
上传用户：shinesyh
AVR single-chip developed by a very low threshold, as long as the computer will be able to study the development of AVR microcontroller. Only a single-chip ISP download beginners line, the editing, debugging of software programs through a direct line into the AVR microcontroller, which can develop AVR Series Single-chip package of a variety of devices. AVR single-chip microcomputer in the industry known as "front-line struggle to seize state power."
标签： single-chip developed threshold the
上传时间： 2013-12-09
上传用户：invtnewer
This is a comparison foundation construction of data example code, the function is quite complete, was myself debugs the successful procedure, might again on Visual c++ the direct movement
标签： construction comparison foundation complete
上传时间： 2013-12-30
上传用户：cxl274287265
频率合成技术在现代电子技术中具有重要的地位。在通信、雷达和导航等设备中，它可以作为干扰信号发生器；在测试设备中，可作为标准信号源，因此频率合成器被人们称为许多电子系统的“心脏”。直接数字频率合成（DDS——Digital Direct Frequency Synthesis）技术是一种全新的频率合成方法，是频率合成技术的一次革命。本文主要分析了DDS的基本原理及其输出频谱特点，并采用VHDL语言在FPGA上实现。对于DDS的输出频谱，一个较大的缺点是：输出杂散较大。针对这一缺点本文使用了两个方法加以解决。首先是压缩ROM查找表，
上传时间： 2017-09-28
上传用户：大三三
direct X9 tutorial1 也就是 directX 9的一个使用手册，我上传这个手册是为了让大家方便查看，如果家里电脑没有安装directX 就很难找到这种官方网站提供的教学信息
标签： directx 9
上传时间： 2015-03-13
上传用户：wai_bomb
Matlab 画三维立体图形 The aim of geom3d library is to handle and visualize 3D geometric primitives such as points, lines, planes, polyhedra... It provides low-level functions for manipulating 3D geometric primitives, making easier the development of more complex geometric algorithms. Some features of the library are: - creation of various shapes (3D points, 3D lines, planes, polyhedra...) through an intuitive syntax. Ex: createPlane(p1, p2, p3) to create a plane through 3 points. - derivation of new shapes: intersection between 2 planes, intersection between a plane and a line, between a sphere and a line... - functions for 3D polygons and polyhedra. Polyhedra use classical vertex-faces arrays (face array contain indices of vertices), and support faces with any number of vertices. Some basic models are provided (createOctaedron, createCubeoctaedron...), as well as some computation (like faceNormal or centroid) - manipulation of planar transformation. Ex.: ROT = createRotationOx(THETA); P2 = transformPoint3d(P1, ROT); - direct drawing of shapes with specialized functions. Clipping is performed automatically for infinite shapes such as lines or rays. Ex: drawPoint3d([50 50 25; 20 70 10], 'ro'); % draw some points drawLine3d([X0 Y0 Z0 DX DY DZ]); % clip and draw straight line Some functions require the geom2d package. Additional help is provided in geom3d/Contents.m file, as well as summary files like 'points3d.m' or 'lines3d.m'.
标签： Matlab 画三维立体图形
上传时间： 2015-11-02
上传用户：A1321
We introduce a sub-cell WENO reconstruction method to evaluate spatial derivatives in the high-order ADER scheme. The basic idea in our reconstruction is to use only r stencils to reconstruct the point-wise values of solutions and spatial derivatives for the 2r-1 th order ADER scheme in one dimension, while in two dimensions, the dimension-by-dimension sub-cell reconstruction approach for spatial derivatives is employed. Compared with the original ADER scheme of Toro and Titarev (2002) [2] that uses the direct derivatives of reconstructed polynomials for solutions to evaluate spatial derivatives, our method not only reduces greatly the computational costs of the ADER scheme on a given mesh, but also avoids possible numerical oscillations near discontinuities, as demonstrated by a number of one- and two-dimensional numerical tests. All these tests show that the 5th-order ADER scheme based on our sub-cell reconstruction method achieves the desired accuracy, and is essentially non-oscillatory and computationally cheaper for problems with discontinuities.
标签： 高精度格式
上传时间： 2016-01-13
上传用户：ccsdcczd
DSPack是一套使用Direct Show和DirectX技术的类和组件。含全部源码。Delphi7控件。
上传时间： 2018-03-29
上传用户：zhao9m
