16个按键分为数字键和功能键。用来向单片机输入点菜信息，单片机通过键盘扫描得到按键信息，调出对应信息，然后通过LCD显示出来。-16 number keys and function keys are divided into key. Ordering information for input to the MCU, microcontroller scans the keyboard get key information, transfer the corresponding infor