Hello. I am developing a project on nRF52832 using SDK 13, in which I need to transfer up to 300 bytes of data from iOS device via my dedicated app (in the background) to nRF in 10 second cycles. Project is based on ble_peripheral_uart example, so I am writing data into one characteristic.
Because data transfer lasts less than a second, it would be energy efficient to disconnect as soon as all data is sent, but here came the problems. Even if I disconnect from my iOS app, because of the system policy the connection still lasts about 7-10 seconds (known iOS issue).
So, I tried to send special "disconnect packet" to my peripheral, so as soon as it receive packet beginning with "11" it run:
err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
And the disconnection in iOS occurs immediately. However, the cycle seem to work only a few times. Sometimes 2, sometimes 13 - no rules. Then it returns 0x08 error code, and nRF will not start advertising again (BLE_GAP_EVT_DISCONNECTED is not received, but my iPhone shows it's disconnected). I also tried starting additional 1.5s timer on BLE_GAP_EVT_CONNECTED and executing disconnection in timer handler, but the result is the same.
Is there any way to ensure continuous work of my device?