使用74164练级8行*2列键盘的行线，74165连接键盘的列线，编写扫描键盘按键的程序，键码显示在发光二极管上。-8 rows with 74 164* 2 columns leveling line keyboard line 74165 column lines connect the keyboard, writing program scans the keyboard keys, key code displayed on the light-emitting diode.