Odd scanning behaviour since NCS 2.6.1

Hi,

I'm seeing a slow and odd scanning behaviour since I updated my toolchain and NCS to 2.6.1.

To my setup:

  • I have two NRF52840, one acting as peripheral, the other as central.
  • The peripheral is connected to the central with connection parameter: 200ms, latency 9
  • Additional I'm sending an advertisement Beacon every 100ms

In the central I've set the scanning parameter "scan interval" and "scan window" to 200. According to this post and the answer this is the right way to do it. Also I have a name and a mac filter running. https://devzone.nordicsemi.com/f/nordic-q-a/109512/scanning-parameter-settings-to-get-the-most-advertisements-but-also-handle-connections

Now to my problem:

  • Flashing the central with NCS 2.5.1 everything works fine. I have a solid connection to the peripheral and almost every advertisement package is received, so ca. 10 per second
  • Flashing the same code with NCS 2.6.1 I'm only receiving 1 or 2 advertisement packages every 3 seconds.

Do you have any idea why the behaviour has changed? Did you change anything in the scanning section during the last release?

Thanks and Best Regards,

Phobios

Parents Reply Children
  • With v2.7.0 it's the same behaviour as with v2.6.1. But I've done some more tests and I have narrowed it down. You see, in my system I have more than one peripheral connected. And as soon as I establish a second connection the problem occurs and I miss a lot of advertisement packages. So the facts are:

    • One peripheral connected and sending out beacons: Everything is fine with 2.5.1, 2.6.1 and 2.7.0
    • Two peripherals or more connected and sending out beacons: Only 2.5.1 works, with 2.6.1 and 2.7.0 I'm getting nearly no advertisement packages

    The peripherals itself all have 2.6.1, and the advertisements are sending out fine (checked with mobile phone and nrf Connect App)

  • Have you tried other scan parameters besides interval = window = 200ms?

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