这是介绍系统按键的软件设计，有各种各样的方案

8x8按键扫描，用PIC单片机的PD口作为列，PB口作为行，逐行扫描，获取行码，列码。然后查表取键值- the 8x8 pressed key scanning, takes the keycode

CH451键盘扫描显示程序代码。可扫描数码管显示和键盘按键。-Internally, a common process of every XIM is to translate keyboard scan code into keycode and then to keysym, by calling XKB, whose process detail has been described in previous sections