按键按照接口原理又可分为编码键盘与非编码键盘两类,全编码键盘由专门的芯片实现识键及输出相应的编码,一般还具有去抖动和多键、窜键等保护电路,这种键盘使用方便,硬件开销大,一般的小型嵌入式应用系统较少采用。非编码键盘由于其经济实用,较多地应用于单片机系统中。 Keys in accordance with the interface principle can be divided into two types of coding keyboard and non-coding keyboard, full-coded keyboard by a special chip to achieve knowledge-based output and the corresponding code, the general also has to jitter and multi-key channeling keys and other protection circuits, this Keyboard easy to use, hardware overhead, the general small embedded applications less used. Non-coding keyboard due to its economical and practical, more used in SCM system.