nRF51822 S110 - TX Buffer leak when disconnected by Central?

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Carles — Fri, 19 Dec 2014 13:26:59 GMT

Hi Joe,

Sorry for the late reply.

Yes, this is fixed in 7.1.0.

Carles

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Joe Merten — Sat, 13 Dec 2014 13:15:18 GMT

Could you confirm that this issue is fixed in current S110 V7.1.0?

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Lucas — Sat, 13 Dec 2014 02:25:54 GMT

I think this needs to be included. In your next softdevice and should be considered. It is a bit odd that the user has no way to figure out how many available buffers there are. The counting mechanism to handle the number of remaining tx buffers seems risky given issues like this exist...

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Joe Merten — Wed, 02 Jul 2014 21:44:18 GMT

Chales said: Please see my extended explanation on my edited answer above.

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Joe Merten — Wed, 02 Jul 2014 21:41:11 GMT

It's a special (exception) handling within a real use case. In some cases (e.g. error states), the central might initiate a disconnect from peripheral, regardless if the peripheral currently sends a bunch of notifications.

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Carles — Mon, 30 Jun 2014 15:09:11 GMT

Sorry John, but this is not under consideration at this point. We will however correct the issue.

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Asbjørn Sæbø — Fri, 27 Jun 2014 15:15:20 GMT

Hi, Joe,

Is what you are doing a real use case, or are you just testing the limits of the system?

Asbjørn

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

Carles — Fri, 27 Jun 2014 07:37:50 GMT

Hi Joe,

Thanks for the detailed report. We are currently looking into this.

UPDATE:

We have analyzed the issue and can confirm that it is indeed present. However, this is not considered critical at this point because the invalid buffer handling is reset after a subsequent reconnection and disconnection. The best way to avoid being affected by the issue is to regularly check for BLE_GAP_EVT_DISCONNECTED events while sending data, so that the interval between the actual disconnection of the link and the moment the application realizes it and stops sending data is as short as possible.

Unfortunately your report came too late to include this in the upcoming 7.0.0 release, but it will be corrected internally and be included in all future S110 releases.

I would like to thank you for your help in uncovering this problem, and hope you can work around it as best as possible until a complete fix is available.

Please let us know if you need more information.

Carles

RE: nRF51822 S110 - TX Buffer leak when disconnected by Central?

John Miller — Tue, 24 Jun 2014 09:24:04 GMT

Could Nordic maybe provide a API function call to determine the count of free tx buffers in Softdevice version 7 ?