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.
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