使用VHDL语言编写的十二进制计数器，有异步清零、同步置数的功能、-Using the VHDL language of the 10 binary counter, there are asynchronous clears, synchronous set the number of functions,

12进制计数器工程，用xilinx ISE设计，供初学者学习-12 hex counter project using xilinx the ISE design for beginners to learn