nRF52840 BLE disconnect after 2 minutes

RE: nRF52840 BLE disconnect after 2 minutes

Tosa — Thu, 03 Dec 2020 05:28:56 GMT

It was an application error in my port from the nRF52832 board to the nRF52840 board. The power management chip had changed and I had changed some startup code incorrectly, leading to a call for advertising to restart, and hence the disconnect. RTT Viewer showed NRF_ERR_CONN_COUNT, helping me to trace down this error. Thanks for your tips in looking for application rather than crystal issues.

RE: nRF52840 BLE disconnect after 2 minutes

Edvin — Tue, 01 Dec 2020 13:23:37 GMT

The unmodified HRS example shouldn't disconnect after 2 minutes. Does it do that in your case?

Possible reasons:

-As awneil says, most examples go to sleep if they don't connect within a couple of minutes (180 seconds to be accurate). This comes from the advertising timeout event. So if you e.g. added support for more connections, and start advertising after you have connected, and this advertisement times out the timeout event may still trigger sleep mode (which is basically turning off the chip). Perhaps this is what's going on?

-Another reason may be that the peripheral doesn't like the connection parameters (connection interval is not within the min-max settings), and the peripheral decides to disconnect after a couple of retries.

-Some other kind of timeout.

Can you please check the log from the nRF? Do you see the disconnect event, or do you just see a reset?

If you see a disconnect, can you please check the disconnect reason? (Let me know if you don't know how to check this on the nRF. It should be mentioned in a fair amount of tickets here on DevZone).

Best regards,

Edvin

RE: nRF52840 BLE disconnect after 2 minutes

Tosa — Tue, 01 Dec 2020 02:03:33 GMT

it is a custom FW (that is based on the HRS example). It does not go to sleep nor disconnect on my nRF52832 system, so I don't expect it to disconnect on the nRF52840 system either.

RE: nRF52840 BLE disconnect after 2 minutes

awneil — Tue, 01 Dec 2020 00:54:08 GMT

Are you basing your work on a Nordic example?

Lots of the Nordic examples do go to sleep after something like 2 minutes - have you left that in ... ?