CC2540: Accessing the Bluetooth Clock

sd26

Part Number: CC2540

Hello,

How can I access the Bluetooth Clock i.e Internal System Clock on CC2540 ? I came across HCI_READ_CLOCK which is for classic bluetooth. Is there any such way for CC2540 ?

Thank you

over 7 years ago

0 Tim C over 7 years ago

TI__Mastermind 34660 points

Hello. The Bluetooth stack uses Timer 2 for the MAC timer so you can read these registers to get the system time. See the "Timer 2 (MAC Timer)" section of the Chip User's Guide: www.ti.com/.../swru191f.pdf

Note that you should definitely not write to any of these registers as it will likely break the timing of the controller.

What exactly are you trying to accomplish? It may be better to use one of the other timers for your own use.

0 sd26 over 7 years ago in reply to Tim C

Prodigy 50 points

Hello Tim,

As mentioned in Health Device Profile Implmentation Guidance Whitepaper (www.bluetooth.org/.../downloaddoc.ashx. under Clock Synchronization Protocol pg. 37. I am trying to implement similar functionality where Master ask Slave to set the Time-Stamp Clock to a specific value in synchronization to the Bluetooth Clock. Thats why Bluetooth Clock access is needed on slave side. and also on Master side when I will send request from Slave side to Master.

0 Tim C over 7 years ago in reply to sd26

TI__Mastermind 34660 points

Ok well then I would recommend reading Timer 2 to get the MAC timer.

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CC2540: Accessing the Bluetooth Clock