packet loss after disconnection?

[nevi]

Hi All! I use nrf51822 with sd s110 to send data to android phone with sd_ble_gatts_hvx. If sd_ble_gatts_hvx returns NRF_SUCCESS then that packet get to TX buffer. I didn't find in the documentation what happens after connection lost. Are that packets (max 7) in the TX buffer lost? Or it will be send after connection?

[FormerMember]

If there are untransmitted packets in the TX buffer where there is a disconnect, those packets will be lost. So, those packets will not be transmitted automatically upon a re-connect. Upon a re-connect, if needed, the packets will have to be put manually into the TX buffer.

[David Edwin]

The BLE_EVT_TX_COMPLETE event signals that the packet has been successfully transmitted and acked by the peer.

[Andrew Ong]

no it doesn't, the BLE_EVT_TX_COMPLETE indicates that it was transmitted, but not acknowledged. only the BLE_GATTS_EVT_HVC event is fired after the BLE Indication acknowledgement.  

[FormerMember]

In BLE, all packets are ack'ed in the link layer. But not necessarily in the application layer: notifications are ack'ed in the link layer, indications are also "ack'ed" in the application layer.