nRF8001: using pipes immediately after re-connecting

[Stephan Walter]

Hi, I'm using an nRF8001 with a locally stored GATT service and security enabled.

I have already established a bond with a master device. The master has enabled notifications/indications for the appropriate characteristics of the GATT service and disconnected.

When I reconnect, I wait until the first bit in the PipesOpen bitmap indicates that pipe discovery has finished and the relevant pipes are open. I then try to send data on a pipe (by Indication or Notification). This data never seems to arrive at the master.

If I wait about 5 seconds after connection has been established, and then send the data, it works fine.

This happens both with the USB dongle from the evaluation board (nRF2739) and with a custom app on an Android smartphone (Galaxy S4).

Am I doing something wrong? As a workaround, I can simply use a delay of about 5s, but I would like to know the reason behind this behavior.

I tried disabling encryption to record a packet trace using a sniffer, but without encryption, the problem does not occur.

Any help would be appreciated. Best regards, --Stephan Walter

[David Edwin]

1. Can you upgrade to the latest version of the master control panel that you use with the nRF2739 and test the behaviour again ?
2. Can you increase the nRF8001 configuration -> Security ->Security Request Delay to 10 seconds and the Bond time out to 600 seconds and re-test.
3. If the above 2 suggestions did not fix the issue. Can you give me a log of the Events that are coming from the nRF8001 on the re-connection. Ideally when a Pipe is open it is available for use.

[Stephan Walter]

Hi, thanks for your reply.

Using MCP 3.6.0 the problem does not occur.

I was using the nRF2739 with an older version of the Python API. Changing Security Request Delay or Bond Timeout did not help. I will try to figure out the difference between how MCP and my script uses the nRF2739.

Best regards, --Stephan Walter