Hi DevZone!
I am developing a Bluetooth beacon that needs to use extended advertising due to the need of periodic advertising. I am using custom board with nrf52820, nRF Connect SDK 2.7.0, Zephyr.
In this case the device should send small packet on Primary Channels (37,38,39) and then the actual packet somewhere in the future on the Secondary Channel.
What I observe is that nrf52820 is not sending that extended packet as soon as possible after the primary packet, instead it seems to change the delay between them ever so slightly every time. It appears to use the whole advertising interval for that, meaning if I set the interval of 100ms the extended packet will be sent as late as 99ms after the primary packet or as soon as 1ms after.
This is terrible for my design where multiple beacons can be in the same area and the device that is scanning for them can be "locked" to one of them for as long as 99ms (scanner will wait for extended packet once it heard the primary packet) not looking for other beacons at that time.
My question is - is there a way to control this behavior? Can I somehow tell the chip to send extended packet on the secondary channel as soon as possible after the primary packet?
I have a device with the chip from other manufacturer which seems to do it that way (so it looks like a difference in Bluetooth stack implementation) and I get much better results with my application.
Any advice would be highly appreciated, thanks!