基于Xilinx Spartan6的复用SPI FLASH储存企业LOGO及其显示方法

本文通过分析图片数据、存储格式、显示标准和读取方式设计了一种显示企业LOGO的方法。该方法使用FPGA通过利用程序存储的SPI FLASH剩余空间存储压缩的图像数据,以双通道读取模式从FLASH中读取,通过彩色表还原颜色,并以高速时钟在LVDS接口的笔记本LCD屏幕上显示,并通过设计程序进行了验证。     

一种透明传输的双向SPI接口的设计与实现

在高速图像/指令扩频无线传输系统中,前向链路主要为遥控指令或者遥控数据(例如航迹),后向链路主要为高速图像数据,无线传输信道为实时双向链路.针对这种前后向链路数据量不对称而又需要实时传输的特点,设计了一种新型的SPI接口,从而较好地解决了此类数据不对称信道中的数据实时双向透明传输的问题.该设计基于FPGA实现,可与绝大多数具有SPI接口的MCU(MPU)主设备进行双向SPI透明传输,而不需要增加任何协议.给出了SPI接口的仿真波形和实现结果,设计完成后经测试证明,该接口完全满足SPI协议串行数据传输的要求,性能可靠.     

TMS320VC5501在线烧写FLASH并自举启动方法研究

为了解决C55X系列DSP系统程序代码的保存问题,文中设计了一种利用JTAG接口,在线烧写DSP片外Flash并实现自举启动的方法。这种在线编程方法利用EMIF接口将TMS320VC5501和FLASH芯片相连接,通过搬移程序将应用程序的已初始化段按照C55X系列DSP引导表格式烧写进外部扩展的FLASH存储器中．从而实现自举启动。该方法为DSP系统的软件维护和升级带来了方便,具有实际应用价值。     

基于MCU IP核的SPI接口ASIC设计及实现

本文介绍了SPI接口的工作原理,详细阐述了该接口工作于主机、从机时各种工作方式下的设计要点、设计思路以及验证过程和结果。用Verilog HDL的可综合语法实现SPI功能描述,用Modelsim进行功能仿真来保证符合设计要求。将SPI模块嵌入到单片机(MCU)中并下载到Xilinx公司的FPGA板VIRTEX-II PRO系列的xc2vp30-ff89上,利用外围电路与具有SPI接口的PIC单片机、STC单片机与FLASH存储器进行各种模式下的通信测试。硬件验证结果表明所设计MCU的SPI接口虽然在具体实现方式上与其他器件可能有所差异,但是完全符合SPI协议。另外,本文介绍了基于MCU的SOC系统采用基于标准单元的方法进行ASIC设计的流程和结果以及用Design compiler单独对SPI模块综合的结果。     

ADSP-21262基于AT25HP512的SPI加载

利用FLASH存储芯片通过SPI接口加载DSP可以有效地降低系统开发成本,但DSP厂商提供的FLASH烧写程序所面向的芯片并不是很多,用户需要针对特殊加载芯片自行开发烧写程序。深入分析了AT25HP512的控制命令和时序结构,提出了修正引导文件的方法,解决了ADSP 21262正确将引导核文件写入AT25HP512的问题,实现了AT25HP512对ADSP 21262的SPI加载,对开发ADSP 21262系统有一定参考意义。     

基于SPI接口安全芯片产品的读卡器研究

由于SPI接口的简单、高速、稳定的特性,在实际中得到了广泛应用,本文介绍了SPI从设备的接口协议,提出了一种基于该SPI协议的读卡器的设计思路,简述了方案的具体实现方法,包括读卡器的硬件设计及软件设计.采用USB即插即用的连接方式,采用CCID标准设备通过USB接口与主机或其它嵌入式主机连接,完成SPI协议的数据通讯,满足了实际的功能需求,对于开发设计相同工作模式下的SPI从设备的程序具有很好的借鉴价值.     

基于XIP FLASH的嵌入式软件设计与应用

传统NOR FLASH并行地址和数据总线的引脚过多，使电路设计的复杂性增大，同时也会增加电路板布线空间。为了解决这一弊端，部分微控制器支持SPI eXecute in Place(XIP)接口，SPI NOR-FLASH应运而生。基于此，文中提出一种嵌入式软件设计方案。该方案充分发挥XIP FLASH片上执行代码的关键属性，利用GNU编译器的工作原理，通过链接器的链接脚本将嵌入式软件程序存储在XIP FLASH中，运行时代码段和只读数据段存放在XIP FLASH中，只需将数据段及操作XIP FLASH的关键代码搬运至RAM中运行。此外，对嵌入式软件的执行流程进行设计与说明。所提方案简单、易操作，已在单相和三相表载波通信单元、Ⅰ型采集器通信单元、Ⅱ型采集器、集中器载波通信单元得到充分验证，可广泛应用于用电信息采集系统、输配电系统的本地通信等领域。     

基于APB总线接口的SPI协议IP核的设计与验证

基于APB总线接口,设计了一种可灵活配置为Master／Slave模式、设置传输速率、支持DMA功能并适用于4种时钟模式的SPI协iK．IP核。首先介绍7SPI协议标准,然后详细说明了该IP核的系统结构、接口信号和子模块设计,并使用TVerilogHDL语言实现硬件设计。最后通过了FPGA时序仿真,验证了该设计的正确性。该IP核已成功用于一款通信芯片,证明了该IP核在实际工程中的可行性。     

SD存储卡接口SD模式的FPGA实现

SD存储卡接口定义了两种通信模式,SD模式和SPI模式.分析了SD传输协议后,给出了一种SD模式设备接口的设计方案.该设计能够自动解析主机发送的命令并响应,与Flash控制器相连后可以对Flash进行读写操作.为了解决数据存取的时序问题,使用了数据缓存技术.FPGA验证表明,该接口能够被电脑识别为SD卡,达到了设计目标.     

用于SoC的SPI接口设计与验证

给出了一个可用于SoC设计的SPI接口IP核的RTL设计与功能仿真。采用AMBA2．0总线标准来实现SPI接口在外部设备和内部系统之间进行通信,在数据传输部分,摒弃传统的需要一个专门的移位传输寄存器实现串／并转换的设计方法,采用复用寄存器的方法,把移位传输寄存器和发送寄存器结合在一起,提高了传输速度,也节约了硬件资源。采用SoC验证平台进行SoC环境下对IP的验证,在100MHz时钟频率下的仿真和验证结果表明,SPI接口实现了数据传榆,且满足时序设计要求。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

中国建立EB级存储实验室,致力云计算应用(英文)

正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-