The first line will pop up a message on the control nodes' display (if X Window System is active), letting the user know that the laptop is inactive and needs to be powered down.
第一行将在控制节点的界面上弹出消息（如果 X Window System 处于活动状态），从而让用户知道笔记本处于非活动状态并且需要关闭。
2
The 'data' line is set inactive when the start bit (always 0) is placed on the 'data' line.
当开始位(总是0)放置到数据线时，数据线被拉低。
3
The auxiliary device checks the 'clock' line. If the line is inactive, output from the device is not allowed.