本书详细介绍了VHDL硬件描述语言，希望在以后的工作中能用到...

一些简单的VHDL实例，主要是介绍一些基本逻辑们及一些组合、时序电路的例子，供大家参考-Some simple examples of VHDL, mainly to introduce some basic logic and some combination of sequential circuit examples for your reference

Altera DE1平台的数字密码锁设计，可以驱动VGA显示(Altera DE1 platform digital password lock design, can drive VGA display)

说明：  VHDL实现的算术逻辑计算单元（ALU），包括modersim测试文件，即仿真结果。(VHDL implementation of the arithmetic logic calculation unit (ALU), including modersim test file, the simulation results.)

A 4 bit twisted ring counter is a sequential circuit which produces the following sequence of output values: 0000, 1000, 1100, 1110, 1111, 0111, 0011, 0001 and then repeats. Design a circuit for a 4 bit twisted ring counter that uses four D flip flops. Draw a state transition diagram, a state table and a schematic for your circuit. Design an alternate implementation using just three flip flops and draw a state transition diagram, state table and a schematic for your circuit. If your designs are extended to implement an n bit twisted ring counter, how many flip flops are required using each of the two approaches. In what situations would you prefer the first method? In what situations would you prefer the second?

基于AT89C51的密码锁（掉电可记忆密码）的程序(Based on AT89C51 lock (down to remembering passwords) program)

FPGA实现SPI接口的从机功能，接收和发送全双工运行，接收到的数据以八位LED灯显示(FPGA to achieve the SPI interface the machine function, receive and send full-duplex operation, the received data to eight LED lights)

说明：  基于RTL8211以太网芯片开发的以太网通信代码，使用Quartus编程，FPGA板子为开发者(Ethernet communication code based on rtl8211 Ethernet chip, using quartus programming, FPGA board for developers)

基于FPGA的JPEG图像压缩芯片设计 -FPGA-based JPEG image compression chip design

it is a new describng system for it field

Vhdl code for aarithmetic logic unit