針對傳統集成電路(ASIC)功能固定、升級困難等缺點,利用FPGA實現了擴頻通信芯片STEL-2000A的核心功能。使用ISE提供的DDS IP核實現NCO模塊,在下變頻模塊調用了硬核乘法器并引入CIC濾波器進行低通濾波,給出了DQPSK解調的原理和實現方法,推導出一種簡便的引入?仔/4固定相移的實現方法。采用模塊化的設計方法使用VHDL語言編寫出源程序,在Virtex-II Pro 開發板上成功實現了整個系統。測試結果表明該系統正確實現了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.
本文利用Verilog HDL 語言自頂向下的設計方法設計多功能數字鐘,突出了其作為硬件描述語言的良好的可讀性、可移植性和易理解等優點,并通過Altera QuartusⅡ 4.1 和ModelSim SE 6.0 完成綜合、仿真。此程序通過下載到FPGA 芯片后,可應用于實際的數字鐘顯示中。
關鍵詞:Verilog HDL;硬件描述語言;FPGA
Abstract: In this paper, the process of designing multifunctional digital clock by the Verilog HDL top-down design method is presented, which has shown the readability, portability and easily understanding of Verilog HDL as a Hard description language. Circuit synthesis and simulation are performed by Altera QuartusⅡ 4.1 and ModelSim SE 6.0. The program can be used in the truly digital clock display by downloading to the FPGA chip.
Keywords: Verilog HDL;Hardware description language;FPGA
tty驅動 * This driver shows how to create a minimal tty driver. It does not rely on * any backing Hardware, but creates a timer that emulates data being received * from some kind of Hardware.
This companion disc contains the source code for the sample
programs presented in INSIDE VISUAL C++ 5.0, as well as pre-
compiled copies of the programs.
To copy all of the sample code onto your Hard disk, run the
SETUP.EXE program and follow the instructions that appear on
the screen. The sample code requires about 10 MB of Hard disk
space.
See Appendix B for a description of the programs included
on this companion disk. RESOURCE.WRI identifies other books
and resources for Internet programming. WEBHELP.HLP contains
an introduction to the World Wide Web. TCPMAN.HLP provides
detailed instructions to help you use the Trumpet Winsock
included on this disk. Use the Program Manager s File menu
Run option to execute the SETUP.EXE program found on this
disk. SETUP.EXE will install the programs on your Hard drive
and create an Internet Programming group window.
Internet編程技術 [配套程序]
[涉及平臺] VC
[作者] void
[文件大小] 1032K
This a online education system that has not been completed yet.We have a long way to go to consummate this system.Let s work Hard together and obtain more and more knowledge !
Many programs today suffer from the fact that their users have to connect using IP addresses. This is impossible for dialup users, whose IPs change all the time, and painful for LAN users who don t know their IP addresses or whose addresses also change. In addition, many collaborative programs could benefit from offering friends lists, showing friends as online or offline, providing status information. This kind of functionality is Hard to provide, requiring a dedicated Internet database and a new client - client protocol. But it is offered today through a system called AwareNet, which is offered free of charge and royalty
FLASH文件系統的源碼,Flash memory is a nonvolatile memory, which allows the user
to electrically program (write) and erase information. The
exponential growth of flash memory has made this technology
an indispensable part of hundreds of millions of electronic
devices.
Flash memory has several significant differences with volatile
(RAM) memory and Hard drive technologies which requires
unique software drivers and file systems. This paper provides
an overview of file systems for flash memory and focuses on
the unique software requirements of flash memory devices.