synchronization of 2 BLE boards

[klaus1234]

Hi

I have 2 BLE boards with some environment sensors on them. 

I need to synchronise the 2 boards with < 1 mili second precision.

one board is configured as central, the other as peripheral.

The 2 Boards have to be connected and exchange their sensor values. This means I need to sync them during an already established connection.

Can You think of a way how I can do that?

Thx

[Turbo J]

If its only 2 boards, you could try abusing the fact that a BTLE connection already synchronizes the devices and use the Radio Notification API to tell you when the next radio slot is about to start.

You can also send some time(er values) back and forth.

Environment sensors typically only need second precisition and not ms...

[klaus1234]

How would I send some timer values furth and back? Using a charachteristic?

Ok Environment sensors is the wrong term. I have some ADC's measuring some physical data with upto 1kHz.

thx

[hmolesworth]

Maybe have a look through this post and git repo:

wireless-timer-synchronization-among-nrf5-devices

nRF5-ble-timesync-demo