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.
上传时间: 2013-11-24
上传用户:18707733937
本文简单讨论并总结了VHDL、Verilog,System verilog 这三中语言的各自特点和区别As the number of enhancements to variousHardware Description Languages (HDLs) hasincreased over the past year, so too has the complexityof determining which language is best fora particular design. Many designers and organizationsare contemplating whether they shouldswitch from one HDL to another.
标签: Verilog verilog System VHDL
上传时间: 2014-03-03
上传用户:zhtzht
Field Programmable Gate Arrays (FPGAs) are becoming a critical part of every system design. Many vendors offer many different architectures and processes. Which one is right for your design? How do you design one of these so that it works correctly and functions as you expect in your entire system? These are the questions that this paper sets out to answer.
上传时间: 2013-10-22
上传用户:lmq0059
针对传统集成电路(ASIC)功能固定、升级困难等缺点,利用FPGA实现了扩频通信芯片STEL-2000A的核心功能。使用ISE提供的DDS IP核实现NCO模块,在下变频模块调用了硬核乘法器并引入CIC滤波器进行低通滤波,给出了DQPSK解调的原理和实现方法,推导出一种简便的引入?仔/4固定相移的实现方法。采用模块化的设计方法使用VHDL语言编写出源程序,在Virtex-II Pro 开发板上成功实现了整个系统。测试结果表明该系统正确实现了STEL-2000A的核心功能。 Abstract: To overcome drawbacks of ASIC such as fixed functionality and upgrade difficulty, FPGA was used to realize the core functions of STEL-2000A. This paper used the DDS IP core provided by ISE to realize the NCO module, called hard core multiplier and implemented CIC filter in the down converter, described the principle and implementation detail of the demodulation of DQPSK, and derived a simple method to introduce a fixed phase shift of ?仔/4. The VHDL source code was designed by modularity method , and the complete system was successfully implemented on Virtex-II Pro development board. Test results indicate that this system successfully realize the core function of the STEL-2000A.
上传时间: 2013-11-19
上传用户:neu_liyan
Modern electronic systems solve so many difficult problems that they often seem like magic. Nonetheless, these systems all have thesame basic limitation: they need a source of electrical power! Most of the time this is a straightforward challenge for the electronicdesigner, because there are many power-delivery solutions. Yet sometimes a device has no direct power source, and running wiresor replacing batteries is impractical. Even when long-life batteries are usable, they eventually need to be replaced, which requires aservice call.
标签: 能量收集
上传时间: 2015-01-03
上传用户:zukfu
The high defi nition multimedia interface (HDMI) is fastbecoming the de facto standard for passing digitalaudio and video data in home entertainment systems.This standard includes an I2C type bus called a displaydata channel (DDC) that is used to pass extended digitalinterface data (EDID) from the sinkdevice (such as adigital TV) to the source device (such as a digital A/Vreceiver). EDID includes vital information on the digitaldata formats that the sink device can accept. The HDMIspecifi cation requires that devices have less than 50pFof input capacitance on their DDC bus lines, which canbe very diffi cult to meet. The LTC®4300A’s capacitancebuffering feature allows devices to pass the HDMI DDCinput capacitance compliance test with ease.
上传时间: 2013-11-21
上传用户:tian126vip
This simple SDI Notepad-like application demonstrates how, taking advantage of the MFC support for Unicode, to Turkmenize labels of the specified menu items. Actually, Turkmen is not supported by Windows 2000, therefore, to create such resources as menu so that strings in Turkmen could be displayed I had to invent an additional technique 这是一个与记事本类似的简单的SDI应用程序,演示了怎样使用MFC来支持 Unicode,对指定的菜单条目进行Turkmenize标签化。实际上,Windwos 2000并不支持Turknen,因此,创建了那些菜单资源以便那些字符串可以在Turknen中显示,为此我必须开发其它的技术。 来源: http://www.codeguru.com/advancedui/SDI_Note.html
标签: Notepad-like demonstrates application advantage
上传时间: 2013-11-26
上传用户:txfyddz
This Unix C code monitors a web server every few minutes by trying to retrieve its home page. It sends you email when it can t connect, and every so often while the server is still down. It sends a final message when it comes back up. If you have email paging, just direct the email to your pager address.
标签: monitors retrieve minutes server
上传时间: 2015-01-11
上传用户:pompey
CZipFile is a lite library that allows you to get information about a zip archive. It is not able to decompress the files, but just retrieves the contents—the file name, file size, and so on.
标签: information CZipFile archive library
上传时间: 2013-12-13
上传用户:ruixue198909
Tug of War(A tug of war is to be arranged at the local office picnic. For the tug of war, the picnickers must be divided into two teams. Each person must be on one team or the other the number of people on the two teams must not differ by more than 1 the total weight of the people on each team should be as nearly equal as possible. The first line of input contains n the number of people at the picnic. n lines follow. The first line gives the weight of person 1 the second the weight of person 2 and so on. Each weight is an integer between 1 and 450. There are at most 100 people at the picnic. Your output will be a single line containing 2 numbers: the total weight of the people on one team, and the total weight of the people on the other team. If these numbers differ, give the lesser first. )
上传时间: 2014-01-07
上传用户:离殇