What can cause missed connection intervals.

[TBone]

Setup: Central app using serialized s120 (2.0.0) with connectivity app.

1. The connection interval is set to 10 ms.
2. Connect to a peripheral
3. From some sniffer data, the connection intervals are 10 / 10 / 10 / 10 / 60 ms. And the pattern repeats forever.

Any ideas what can cause this?

Thanks for any help.

[Hung Bui]

@Tbone: Could you provide the sniffer trace ? If you set it to other connection interval do you observe the same ?

[TBone]

I have sniffer data using a TI dongle. The only way I know to share this data is with an image (screen capture). I'm not sure how to upload an image in this forum.

[Hung Bui]

@TBone: It would be easier if you can have our sniffer trace. To be honest I'm not very familiar with the TI Packet Sniffer. But want thing you may want to check is that if actually the sniffer missing the connection event, not the nRF51 it self. You can detect that by looking at the SN and NESN.

btw, which peripheral did you connect to ?

[TBone]

Answered by the wonderful Nordic support team. (Kenneth, in this case.)

I was still scanning, and I had the scanning interval set to 50 ms every 100 ms. This explains the symptoms exactly! The radio can only be doing one thing at a time!