If the host pulls clock low before the first high-to-low clock transition, or after the falling edge of the last clock pulse, the keyboard/ mouse does not need to retransmit any data.

• 如果在第一个高->时钟跳变时，（者在最后一个时钟脉冲的下降沿之后）机将时钟拉低，键盘/标不必重新传输任何数据。