The Virtex-4 features, such as the programmable IDELAY and built-in FIFO support, simplifythe bridging of a high-speed, PCI-X core to large amounts of DDR-SDRAM memory. Onechallenge is meeting the PCI-X target initial latency specification. PCI-X Protocol Addendum tothe PCI Local Bus Specification Revision 2.0a ([Ref 6]) dictates that when a target signals adata transfer, "the target must do so within 16 clocks of the assertion of FRAME#." PCItermination transactions, such as Split Response/Complete, are commonly used to meet thelatency specifications. This method adds complexity to the design, as well as additional systemlatency. Another solution is to increase the ratio of the memory frequency to the PCI-X busfrequency. However, this solution increases the required power and clock resource usage.
上傳時間: 2013-11-24
上傳用戶:18707733937
波長信號的解調(diào)是實(shí)現(xiàn)光纖光柵傳感網(wǎng)絡(luò)的關(guān)鍵,基于現(xiàn)有的光纖光柵傳感器解調(diào)方法,提出一種基于FPGA的雙匹配光纖光柵解調(diào)方法,此系統(tǒng)是一種高速率、高精度、低成本的解調(diào)系統(tǒng),并且通過引入雙匹配光柵有效地克服了雙值問題同時擴(kuò)大了檢測范圍。分析了光纖光柵的測溫原理并給出了該方案軟硬件設(shè)計,綜合考慮系統(tǒng)的解調(diào)精度和FPGA的處理速度給出了基于拉格朗日的曲線擬合算法。 Abstract: Sensor is one of the most important application of the fiber grating. Wavelength signal demodulating is the key techniques to carry out fiber grating sensing network, based on several existing methods of fiber grating sensor demodulation inadequate, a two-match fiber grating demodulation method was presented. This system is a high-speed, high precision, low-cost demodulation system. And by introducing a two-match grating effectively overcomes the problem of double value while expands the scope of testing. This paper analyzes the principle of fiber Bragg grating temperature and gives the software and hardware design of the program. Considering the system of demodulation accuracy and processing speed of FPGA,this paper gives the curve fitting algorithm based on Lagrange.
標(biāo)簽: FPGA 光纖光柵 解調(diào)系統(tǒng)
上傳時間: 2013-10-10
上傳用戶:zxc23456789
The LogiCORE™ GTP Wizard automates the task of creating HDL wrappers to configure the high-speed serial GTP transceivers in Virtex™-5 LXT and SXT devices. The menu-driven interface allows one or more GTP transceivers to be configured using pre-definedtemplates for popular industry standards, or from scratch, to support a wide variety of custom protocols.The Wizard produces a wrapper, an example design, and a testbench for rapid integration and verification of the serial interface with your custom function Features• Creates customized HDL wrappers to configureVirtex-5 RocketIO™ GTP transceivers• Users can configure Virtex-5 GTP transceivers toconform to industry standard protocols usingpredefined templates, or tailor the templates forcustom protocols• Included protocol templates provide support for thefollowing specifications: Aurora, CPRI, FibreChannel 1x, Gigabit Ethernet, HD-SDI, OBSAI,OC3, OC12, OC48, PCI Express® (PCIe®), SATA,SATA II, and XAUI• Automatically configures analog settings• Each custom wrapper includes example design, testbench; and both implementation and simulation scripts
標(biāo)簽: Transceiver Virtex Wizar GTP
上傳時間: 2013-10-20
上傳用戶:dave520l
減小電磁干擾的印刷電路板設(shè)計原則 內(nèi) 容 摘要……1 1 背景…1 1.1 射頻源.1 1.2 表面貼裝芯片和通孔元器件.1 1.3 靜態(tài)引腳活動引腳和輸入.1 1.4 基本回路……..2 1.4.1 回路和偶極子的對稱性3 1.5 差模和共模…..3 2 電路板布局…4 2.1 電源和地…….4 2.1.1 感抗……4 2.1.2 兩層板和四層板4 2.1.3 單層板和二層板設(shè)計中的微處理器地.4 2.1.4 信號返回地……5 2.1.5 模擬數(shù)字和高壓…….5 2.1.6 模擬電源引腳和模擬參考電壓.5 2.1.7 四層板中電源平面因該怎么做和不應(yīng)該怎么做…….5 2.2 兩層板中的電源分配.6 2.2.1 單點(diǎn)和多點(diǎn)分配.6 2.2.2 星型分配6 2.2.3 格柵化地.7 2.2.4 旁路和鐵氧體磁珠……9 2.2.5 使噪聲靠近磁珠……..10 2.3 電路板分區(qū)…11 2.4 信號線……...12 2.4.1 容性和感性串?dāng)_……...12 2.4.2 天線因素和長度規(guī)則...12 2.4.3 串聯(lián)終端傳輸線…..13 2.4.4 輸入阻抗匹配...13 2.5 電纜和接插件……...13 2.5.1 差模和共模噪聲……...14 2.5.2 串?dāng)_模型……..14 2.5.3 返回線路數(shù)目..14 2.5.4 對板外信號I/O的建議14 2.5.5 隔離噪聲和靜電放電ESD .14 2.6 其他布局問題……...14 2.6.1 汽車和用戶應(yīng)用帶鍵盤和顯示器的前端面板印刷電路板...15 2.6.2 易感性布局…...15 3 屏蔽..16 3.1 工作原理…...16 3.2 屏蔽接地…...16 3.3 電纜和屏蔽旁路………………..16 4 總結(jié)…………………………………………17 5 參考文獻(xiàn)………………………17
上傳時間: 2013-10-22
上傳用戶:a6697238
This document provides practical, common guidelines for incorporating PCI Express interconnect layouts onto Printed Circuit Boards (PCB) ranging from 4-layer desktop baseboard designs to 10- layer or more server baseboard designs. Guidelines and constraints in this document are intended for use on both baseboard and add-in card PCB designs. This includes interconnects between PCI Express devices located on the same baseboard (chip-to-chip routing) and interconnects between a PCI Express device located “down” on the baseboard and a device located “up” on an add-in card attached through a connector. This document is intended to cover all major components of the physical interconnect including design guidelines for the PCB traces, vias and AC coupling capacitors, as well as add-in card edge-finger and connector considerations. The intent of the guidelines and examples is to help ensure that good high-speed signal design practices are used and that the timing/jitter and loss/attenuation budgets can also be met from end-to-end across the PCI Express interconnect. However, while general physical guidelines and suggestions are given, they may not necessarily guarantee adequate performance of the interconnect for all layouts and implementations. Therefore, designers should consider modeling and simulation of the interconnect in order to ensure compliance to all applicable specifications. The document is composed of two main sections. The first section provides an overview of general topology and interconnect guidelines. The second section concentrates on physical layout constraints where bulleted items at the beginning of a topic highlight important constraints, while the narrative that follows offers additional insight.
標(biāo)簽: pci PCB 設(shè)計規(guī)范
上傳時間: 2014-01-24
上傳用戶:s363994250
The data plane of the reference design consists of a configurable multi-channel XBERT modulethat generates and checks high-speed serial data transmitted and received by the MGTs. Eachchannel in the XBERT module consists of two MGTs (MGTA and MGTB), which physicallyoccupy one MGT tile in the Virtex-4 FPGA. Each MGT has its own pattern checker, but bothMGTs in a channel share the same pattern generator. Each channel can load a differentpattern. The MGT serial rate depends on the reference clock frequency and the internal PMAdivider settings. The reference design can be scaled anywhere from one channel (two MGTs)to twelve channels (twenty-four MGTs).
標(biāo)簽: RocketIO Virtex XAPP 713
上傳時間: 2013-12-25
上傳用戶:jkhjkh1982
C++完美演繹 經(jīng)典算法 如 /* 頭文件:my_Include.h */ #include <stdio.h> /* 展開C語言的內(nèi)建函數(shù)指令 */ #define PI 3.1415926 /* 宏常量,在稍后章節(jié)再詳解 */ #define circle(radius) (PI*radius*radius) /* 宏函數(shù),圓的面積 */ /* 將比較數(shù)值大小的函數(shù)寫在自編include文件內(nèi) */ int show_big_or_small (int a,int b,int c) { int tmp if (a>b) { tmp = a a = b b = tmp } if (b>c) { tmp = b b = c c = tmp } if (a>b) { tmp = a a = b b = tmp } printf("由小至大排序之后的結(jié)果:%d %d %d\n", a, b, c) } 程序執(zhí)行結(jié)果: 由小至大排序之后的結(jié)果:1 2 3 可將內(nèi)建函數(shù)的include文件展開在自編的include文件中 圓圈的面積是=201.0619264
標(biāo)簽: my_Include include define 3.141
上傳時間: 2014-01-17
上傳用戶:epson850
數(shù)字運(yùn)算,判斷一個數(shù)是否接近素數(shù) A Niven number is a number such that the sum of its digits divides itself. For example, 111 is a Niven number because the sum of its digits is 3, which divides 111. We can also specify a number in another base b, and a number in base b is a Niven number if the sum of its digits divides its value. Given b (2 <= b <= 10) and a number in base b, determine whether it is a Niven number or not. Input Each line of input contains the base b, followed by a string of digits representing a positive integer in that base. There are no leading zeroes. The input is terminated by a line consisting of 0 alone. Output For each case, print "yes" on a line if the given number is a Niven number, and "no" otherwise. Sample Input 10 111 2 110 10 123 6 1000 8 2314 0 Sample Output yes yes no yes no
上傳時間: 2015-05-21
上傳用戶:daguda
The HD66773, controller driver LSI, displays 132RGB-by-176 dot graphics on TFT displays in 260,000 colors. The HD66773’s bit-operation functions, 18-bit high-speed bus interface, and high-speed RAMwrite functions enable efficient data transfer and high-speed rewriting of data to the graphic RAM.
標(biāo)簽: displays controller graphics RGB-by
上傳時間: 2014-06-19
上傳用戶:stvnash
源代碼\用動態(tài)規(guī)劃算法計算序列關(guān)系個數(shù) 用關(guān)系"<"和"="將3個數(shù)a,b,c依次序排列時,有13種不同的序列關(guān)系: a=b=c,a=b<c,a<b=v,a<b<c,a<c<b a=c<b,b<a=c,b<a<c,b<c<a,b=c<a c<a=b,c<a<b,c<b<a 若要將n個數(shù)依序列,設(shè)計一個動態(tài)規(guī)劃算法,計算出有多少種不同的序列關(guān)系, 要求算法只占用O(n),只耗時O(n*n).
標(biāo)簽: lt 源代碼 動態(tài)規(guī)劃 序列
上傳時間: 2013-12-26
上傳用戶:siguazgb
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