说明：  仪器仪表键盘显示模拟系统，用AT89S52芯片作为系统的CPU，控制系统的按键及显示器部分。用8路同相三态双向总线收发器74LS245芯片驱动LED。4X4矩阵键盘作为系统人机交互的重要部分，用于向单片机应用系统输入数据或控制信息，设计4X4矩阵键盘分别对应键码“0-F”。系统可以实现的基本功能包括开机LCD液晶屏幕显示“大专05电子信息X班XXX毕业设计”信息；按下任意一个按键，LCD液晶屏幕显示相应按键的信息。在基本功能的基础上还增加了一个扩展功能，即增加一个LED数码管同步显示相应键码
(Show the simulated keyboard instrumentation systems, using AT89S52 chip as a system CPU, system control buttons and display parts. With 8-phase three-state bidirectional bus transceiver 74LS245 chip-driven LED. 4X4 matrix keyboard system as an important part of human-computer interaction, single-chip microcomputer application system used to input data or control information, the design of 4X4 matrix keyboard key code corresponding to )