如计算器输入数据形式相同 从右至左 使用行列扫描方法中断方式可以有效提供cpu工作效率，在有按键动作时才扫描，平时不进行扫描工作-Such as computer input data in the form of the same the right to the left and right to use the ranks of the scanning method can effectively provide the CPU work efficiency, when there