nrf51 does not respond to bluetooth message

RE: nrf51 does not respond to bluetooth message

run_ar — Fri, 31 Mar 2017 08:55:31 GMT

@toney1980 Which iOS app are you using? Do you see the same reconnect issue if you test with another platform. e.g. nRF connect for PC or Android?

RE: nrf51 does not respond to bluetooth message

endnode — Fri, 24 Mar 2017 15:00:51 GMT

iOS behavior with BLE when it is in Central role used to be following (probably still is):

Once mobile pp on top of iOS asks for link termination it can take up to several seconds (10?) before BLE chipset really sends LL_TERMINATE.
However if Peripheral device on the other side of the link sends LL_TERMINATE it disconnects pretty much immediately.

So the workaround is to define custom indication/command on BT LE APP layer (on top of GATT) which signals that device (be it iOS or anything else) wants to disconnect quickly. Then mobile app developer can use it to speed up the process (if Peripheral side implements it of course;).

RE: nrf51 does not respond to bluetooth message

toney1980 — Fri, 24 Mar 2017 13:48:39 GMT

Yes. I am using the mbed for redbear BLEnano which uses nrf51. Is there any stability issue with using mbed? What I did is to completely quit the iphone App and wait for some time, then start the app again to discover and connect to the nrf51. If the wait time is short, the app works with nrf 51 correctly after the re-connection. If the wait time is long, nrf51 would not respond to ble messages from the app.

RE: nrf51 does not respond to bluetooth message

Petter Myhre — Fri, 24 Mar 2017 10:28:47 GMT

The iPhone will not disconnect straight away even though you close the app. So maybe after a short while you are still connected when you open the app, but after a while you are disconnected, and will have to connect again.

RE: nrf51 does not respond to bluetooth message

endnode — Fri, 24 Mar 2017 10:28:42 GMT

Hard to say from that little snippet (I assume you even don't use nRF5 SDK directly, is it mbed SDK or something else?). Btw. I suggest nRF51 DK as it seems to me little bit more stable with Nordic Sniffer FW and also more flexible (it typically needs to be in almost ideal position between 2 communicating peers and having DK on USB cable works better for me then Dongle plugged into the PC).

RE: nrf51 does not respond to bluetooth message

toney1980 — Fri, 24 Mar 2017 02:05:30 GMT

Thanks for the suggestion. I will buy a dongle or 51 DK to run the sniffer. The symptom here is that after a long wait, the iphone App is still able to discover the nRF51 BLE device as peripheral. So there is advertising RF activity by the nRF51. But the nRF51 will not respond to BLE write from iphone app. I have the following programming structure. The activeloop seems to work fine. But if the program run in the idle loop for some time, I cannot use BLE message from iphone App to switch it back to the active loop. If the program run in the idle loop for a short time period. I can use BLE message from Iphone to switch it back to the active loop. main{ while{ if(activeloop){ // active loop operation performactivefunction(); }else{ // idle power saving loop ble.waitForEvent(); } }

}

RE: nrf51 does not respond to bluetooth message

endnode — Wed, 22 Mar 2017 10:00:01 GMT

Do you have any RF logs (e.g. from Nordic BLE sniffer or similar) which would support your hypothesis that "nRF51 does not respond to any message sent from the iphone App"?