RE: Optimising throughput in case of small data

Tibor Kakonyi — Tue, 09 Mar 2021 16:34:42 GMT

Hi Edvin,

Thank you very much for the clarification!

RE: Optimising throughput in case of small data

Edvin — Tue, 09 Mar 2021 16:10:31 GMT

Hello Tibor,

[quote user=""]I am sending only small, 1-byte pieces of data, but it is critic to send them as quickly as possible.[/quote]

So you don't want to optimize the throughput, but you want to optimize the latency.

You can use 2MBPS if possible, but the difference between 2MBPS and 1MBPS is not very large in this case, since the payload size is so small. The main delay in this case is simply the connection interval, and unfortunately phones are quite strict on connection intevrals. You can request a short connection interval (by adjusting your MIN_CONN_INTERVAL and MAX_CONN_INTERVAL in the peripheral's project), but it is always the central that has the final saying in what connection interval that is used. Typically for phones this is 15ms, but it depends on the phone.

So if the connection interval is fixed to 15ms, then you will have a latency between 1-2ms and 15ms, based on when you queue your data.

For low latency, you should always use notifications from the peripheral to the central.

Best regards,

Edvin