two NRF51822 communication fails sometimes

[phob]

Hi, I am using 2 nrf51822 devices. one is central and other one is peripheral. I am using s130 softdevice. When i was trying to connect NRF51822 to other nrf51822. i tried for 1st time then communication happens. But later communication happens once in 10 time.

But when i was trying to connec NRF51822 with NRF52 DK board NRF51822 was central and NRF52 DK was peripheral. That time communihcation was happening everytime.

What could be the problem.

[endnode]

Sorry but it's hard to say without knowing what exactly you are running on these boards (FW) and what do you mean by "communication fails": in what phase? Can you do radio log with BLE sniffer to see which peer causes the hang? Do you have any debug logs from FWs running on these boards?

[phob]

I am using SDK v12.2.0. I think in the case i mentioned, Central device(NRF51822) is working fine. But when i use second NRF51822 for peripheral then communication is not happening. Not getting connect to central. But When i use NRF52 as peripheral with same code then It works. But i have to use NRF51822 only. Communication fails means they are not at all getting connect. not pairing as well. I have don't have sniffer to capture the log.

[endnode]

Still your description sounds like "my car stopped working please fix it" without saying where you are, what car you have, what is on the panel, what you observed before it stopped and all that to complete stranger over the phone who is thousands miles away. What I want to say is: there can be hundreds of reasons and without precise description what HW board (not just which chip), what FW (not just SDK version) and what use case (= exactly what packets were exchanged over the air or at least some verbose debug trace from the FWs) I cannot help you (and I'm afraid neither do Nordic support team or the rest of the forum).

E.g. if there is no connection is your nRF51 Peripheral advertising? Then you start speaking about pairing but how that could happen if there is no connection link? Really confusing.

[run_ar]

@phob are you using the same sdk for both the nRF51 and nRF52 peripheral? Are they using the same advertisement parameters (interval and timeout) and adv data? did you use an sdk example or a custom application?

[phob]

I am using same SDK for both nrf51 and nrf52 board. I didn't change any parameter from example which were available in SDK.