按键扫描的程序，优化还需要加双重防抖，解释按键的值或者名称-button scanning procedures, optimizing also required to double Fangdou explain the value of the keys or name

arm2440下，linux2.6内核的按键的中断驱动程序（可防抖）以及用户应用测试程序-arm2440 under, linux2.6 kernel driver interrupt button (which can be anti-shake), and user application test procedure