Format of Clock Offset used to obtain CLKE

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.