按键检测VHDL程序，主要实现对开发板按键的检测以及一些时间延迟的信息。程序较全，可以按照不同的开发板设置相应的引脚进行操作。-Key detection VHDL program, the main achievement of some time delay detection and information on the development board keys. Than the whole program, you can set the corresponding pin to