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