RE: Duplicating same data when interval is long

comkuk — Tue, 05 Apr 2016 15:36:30 GMT

Thank you, Terje, for your answer. I did change the connection intervals as 500 ms for min_conn_interval and 1000 ms for max_conn_interval and now I'm seeing the data repeats only two times. How can I make BLE data sent at the same sampling rates I define?

RE: Duplicating same data when interval is long

tesc — Tue, 05 Apr 2016 08:41:21 GMT

I assume that the data is sent during a connection, and not in advertising packets.

This will happen for instance if the connection interval is set to 15 ms and you send the data on every connection event.

While the peripheral can suggest what connection parameters to use, the final decision is made by the central. This means you do not have full control over the connection interval.

It is totally fine to have a higher frequency for connection events than the frequency of the data to be transmitted (i.e. to have a smaller connection interval). One way to send the data is to use notifications. The way that works is that the central enables notifications for a specific characteristic. Every time the value changes the peripheral sends a notification with the new value on the next connection event. Notifications is covered in BLE Characteristics, a beginner's tutorial.

Regards, Terje

RE: Duplicating same data when interval is long

Wojtek — Tue, 05 Apr 2016 08:07:35 GMT

What behavior do you expect?