我采用XC4VSX35或XC4VLX25 FPGA來連接DDR2 SODIMM和元件。SODIMM內(nèi)存條選用MT16HTS51264HY-667(4GB),分立器件選用8片MT47H512M8。設(shè)計(jì)目標(biāo):當(dāng)客戶使用內(nèi)存條時(shí),8片分立器件不焊接;當(dāng)使用直接貼片分立內(nèi)存顆粒時(shí),SODIMM內(nèi)存條不安裝。請問專家:1、在設(shè)計(jì)中,先用Xilinx MIG工具生成DDR2的Core后,管腳約束文件是否還可更改?若能更改,則必須要滿足什么條件下更改?生成的約束文件中,ADDR,data之間是否能調(diào)換? 2、對DDR2數(shù)據(jù)、地址和控制線路的匹配要注意些什么?通過兩只100歐的電阻分別連接到1.8V和GND進(jìn)行匹配 和 通過一只49.9歐的電阻連接到0.9V進(jìn)行匹配,哪種匹配方式更好? 3、V4中,PCB LayOut時(shí),DDR2線路阻抗單端為50歐,差分為100歐?Hyperlynx仿真時(shí),那些參數(shù)必須要達(dá)到那些指標(biāo)DDR2-667才能正常工作? 4、 若使用DDR2-667的SODIMM內(nèi)存條,能否降速使用?比如降速到DDR2-400或更低頻率使用? 5、板卡上有SODIMM的插座,又有8片內(nèi)存顆粒,則物理上兩部分是連在一起的,若實(shí)際使用時(shí),只安裝內(nèi)存條或只安裝8片內(nèi)存顆粒,是否會(huì)造成信號完成性的影響?若有影響,如何控制? 6、SODIMM內(nèi)存條(max:4GB)能否和8片分立器件(max:4GB)組合同時(shí)使用,構(gòu)成一個(gè)(max:8GB)的DDR2單元?若能,則布線阻抗和FPGA的DCI如何控制?地址和控制線的TOP圖應(yīng)該怎樣? 7、DDR2和FPGA(VREF pin)的參考電壓0.9V的實(shí)際工作電流有多大?工作時(shí)候,DDR2芯片是否很燙,一般如何考慮散熱? 8、由于多層板疊層的問題,可能頂層和中間層的銅箔不一樣后,中間的夾層后度不一樣時(shí),也可能造成阻抗的不同。請教DDR2-667的SODIMM在8層板上的推進(jìn)疊層?
上傳時(shí)間: 2013-10-12
上傳用戶:han_zh
UART 4 UART參考設(shè)計(jì),Xilinx提供VHDL代碼 uart_vhdl This zip file contains the following folders: \vhdl_source -- Source VHDL files: uart.vhd - top level file txmit.vhd - transmit portion of uart rcvr.vhd - - receive portion of uart \vhdl_testfixture -- VHDL Testbench files. This files only include the testbench behavior, they do not instantiate the DUT. This can easily be done in a top-level VHDL file or a schematic. This folder contains the following files: txmit_tb.vhd -- Test bench for txmit.vhd. rcvr_tf.vhd -- Test bench for rcvr.vhd.
標(biāo)簽: UART Xilinx VHDL 參考設(shè)計(jì)
上傳時(shí)間: 2013-11-07
上傳用戶:jasson5678
There is no doubt that remote controls are extremely popular and it has become very hard to imagine a world without them. They are used to control all manner of house appliances like the TV set, the stereo, the VCR, and the satellite receiver.
上傳時(shí)間: 2013-11-13
上傳用戶:頂?shù)弥?/p>
This application note describes a reference system which illustrates how to build an embeddedPowerPC® system using the Xilinx 1-Gigabit Ethernet Media Access Controller processor core.This system has the PLB_Gemac configured to use Scatter/Gather Direct Memory Access andthe Serializer/Deserializer (SerDes) interface. This application note describes how to set up thespecific clocking structure required for the SerDes interface and the constraints to be added tothe UCF file. This reference system is complete with a standalone software application to testsome of the main features of this core, including access to registers, DMA capabilities, transmitand receive in loopback mode. This reference system is targeted for the ML300 evaluationboard.
上傳時(shí)間: 2013-11-01
上傳用戶:truth12
本文主要通過介紹PLC通訊的意義和三菱FX系列PLC的四種通訊方式,并重點(diǎn)介紹FX系列PLC與計(jì)算機(jī)無協(xié)議通訊,主要從無協(xié)議通訊的硬件、配線、數(shù)據(jù)寄存器設(shè)置、PLC與計(jì)算機(jī)無協(xié)議通訊的指令用法、PLC程序編寫和計(jì)算機(jī)VB程序的編寫來說明無協(xié)議通訊的過程和一般方法。 My dissertation introduces the significance of PLC communications and the four means of communication of Mitsubishi FX’s PLC, And highlights the no protocol communications of FX series PLC and computer, no protocol communications hardware, wiring, Register data set, and the usage of command about no protocol communications, How to write PLC program and computer VB program to illustrate the process of no protocol communications and general method.
標(biāo)簽: PLC 三菱FX系列 計(jì)算機(jī) 協(xié)議
上傳時(shí)間: 2014-11-29
上傳用戶:Jerry_Chow
This application note provides step-by-step instructions on how to recreate a Tri-Mode Ethernet(TEMAC) performance testing system using the ML405 board and MontaVista Linux 4.0. Thisapplication note shows how to set up a simple EDK Base System Builder system on the ML405Evaluation Platform and run performance tests. The network architecture for the test isdescribed. A system is built and downloaded into the FPGA. A MontaVista Linux kernel isconfigured, built, and downloaded into the ML405 Evaluation Platform. The instructions forobtaining and setting up the software used to perform the measurements, netperf, are given.
標(biāo)簽: Virtex TEMAC XAPP 1023
上傳時(shí)間: 2013-11-11
上傳用戶:saharawalker
With the Altera Nios II embedded processor, you as the system designercan accelerate time-critical software algorithms by adding custominstructions to the Nios II processor instruction set. Using custominstructions, you can reduce a complex sequence of standard instructionsto a single instruction implemented in hardware. You can use this featurefor a variety of applications, for example, to optimize software innerloops for digital signal processing (DSP), packet header processing, andcomputation-intensive applications. The Nios II configuration wizard,part of the Quartus® II software’s SOPC Builder, provides a graphicaluser interface (GUI) used to add up to 256 custom instructions to theNios II processor
上傳時(shí)間: 2013-11-07
上傳用戶:swing
The #1 Step-by-Step Guide to labviewNow Completely Updated for labview 8! Master labview 8 with the industry's friendliest, most intuitive tutorial: labview for Everyone, Third Edition. Top labview experts Jeffrey Travis and Jim Kring teach labview the easy way: through carefully explained, step-by-step examples that give you reusable code for your own projects! This brand-new Third Edition has been fully revamped and expanded to reflect new features and techniques introduced in labview 8. You'll find two new chapters, plus dozens of new topics, including Project Explorer, AutoTool, XML, event-driven programming, error handling, regular expressions, polymorphic VIs, timed structures, advanced reporting, and much more. Certified labview Developer (CLD) candidates will find callouts linking to key objectives on NI's newest exam, making this book a more valuable study tool than ever. Not just what to d why to do it! Use labview to build your own virtual workbench Master labview's foundations: wiring, creating, editing, and debugging VIs; using controls and indicators; working with data structures; and much more Learn the "art" and best practices of effective labview development NEW: Streamline development with labview Express VIs NEW: Acquire data with NI-DAQmx and the labview DAQmx VIs NEW: Discover design patterns for error handling, control structures, state machines, queued messaging, and more NEW: Create sophisticated user interfaces with tree and tab controls, drag and drop, subpanels, and more Whatever your application, whatever your role, whether you've used labview or not, labview for Everyone, Third Edition is the fastest, easiest way to get the results you're after!
標(biāo)簽: Everyone LabVIEW for 英文
上傳時(shí)間: 2013-10-14
上傳用戶:shawvi
The LTC®3207/LTC3207-1 is a 600mA LED/Camera driverwhich illuminates 12 Universal LEDs (ULEDs) and onecamera fl ash LED. The ULEDs are considered universalbecause they may be individually turned on or off, setin general purpose output (GPO) mode, set to blink at aselected on-time and period, or gradate on and off at aselected gradation rate. This device also has an externalenable (ENU) pin that may be used to blink, gradate, orturn on/off the LEDs without using the I2C bus. This may beuseful if the microprocessor is in sleep or standby mode. Ifused properly, these features may save valuable memoryspace, programming time, and reduce the I2C traffi c.
上傳時(shí)間: 2014-01-04
上傳用戶:LANCE
This book evolved over the past ten years from a set of lecture notes developed while teaching the undergraduate Algorithms course at Berkeley and U.C. San Diego. Our way of teaching this course evolved tremendously over these years in a number of directions, partly to address our students' background (undeveloped formal skills outside of programming), and partly to reect the maturing of the eld in general, as we have come to see it. The notes increasingly crystallized into a narrative, and we progressively structured the course to emphasize the ?story line? implicit in the progression of the material. As a result, the topics were carefully selected and clustered. No attempt was made to be encyclopedic, and this freed us to include topics traditionally de-emphasized or omitted from most Algorithms books.
標(biāo)簽: Algorithms 算法
上傳時(shí)間: 2013-11-11
上傳用戶:JamesB
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