Format of Clock Offset used to obtain CLKE

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本文探讨了蓝牙设备中从属设备如何通过调整其本机时钟(CLKN)与主设备进行同步的方法。文中提到从属设备通过增加一个偏移量来与其自身的CLKN相加实现同步，并解释了该偏移量不一定是312.5us的整数倍。

Format of Clock Offset used to obtain CLKE

Original Post: Sync between master and slaves (SIG Forum) Date: 2000-07-28

The native clock (CLKN) ticks every 312.5us for each bluetooth device. Slaves can sync to master by adding an offset to it's own CLKN. By what kind of value is the offset value. Is it a factor of the actual clock (i.e. units of 312.5us)?

The response is that N (the offset value) may not be an integer like CLK is. If you look at spec pp.87, section 9.1, it says "The master never adjusts its system clock during the existence of the Piconet: it keeps an exact interval of M*625us. The slaves adapt their native clocks with a timing offset in order to match the master clock." It doesn't say the offset must be an interger number of 312.5us, it only says the offset must be found to match the master's.

Thus any integer value (10us, 22us etc.) could be used to adopt the slaves native clock.