In this example w ill interface the PS/2 port to a PS/2 keyboard, also known as an AT keyboard. The example will not apply to the newer USB keyboards, or to the older, obsolete XT keyboard. Keyboards contain their own microprocessors that conti

采用VHDL这一简单实用的硬件描述语言，对常见的4*4键盘扫描显示作了简单的描述，重点是扫描、显示的原理过程，其中采用了很多的进程语句。-a very simple and common keyboard in laboratory,we use the specific hardware language,namely,the VHDL.we describle the specific working process.