键盘扫描程序 C51单片机可以直接下载，绝对好用。-Keyboard scanning procedures C51 microcontroller can directly download absolutely easy to use.

ps2 程序及接线图，还有C51程序，适合初学者学习-PS2 program and wiring diagram, and the C51 program, suitable for beginners to learn PS2 program and wiring diagram, and the C51 program, suitable for beginners to learn