RE: Ble connection interval

ovrebekk — Thu, 04 Nov 2021 12:18:48 GMT

Hi Dipak

There are various factors that affect the total transmission time, but when writing data using commands (rather than requests) the ACK will be sent immediately, and there is no need to wait for the next connection event in order to receive the ACK.

Assuming you are using a 7.5ms connection interval this means you have a typical worst case transmission time of around 7.5ms (assuming you have a good link with no packet loss), plus some overhead to transmit and process the packet.

The reason I say worst case here is that if you happen to upload a packet just before the next connection event is about to occur, the wait time could be shorter.

Also, most BLE stacks allow you to buffer multiple packets in memory and send them one after the other on the next available connection event, in order to increase data throughput. This means that you are not limited to send a single packet pr connection event, but that you can send multiple packets in fast succession.

Best regards
Torbjørn