Reducing the characteristic discovery time for peripheral device

[Srikanth]

We have a nrf52840 in peripheral mode and with with custom services characteristics added. we want to reduce the over all connection time when we try to connect with central device.

can you suggest us some suggestions to reduce the connection time  ? ( we can see at our end connection time nearly taking 1sec)

Thanks,

Srikanth R V

[Srikanth]

Hi karl,

please find the attached image and highlighted the  discovery events after connection which are consuming more time from central device.

it looks like the default services 0x1800, 0x1801 is taking more time for discovery. what can be done to prevent this.

Thanks,

Srikanth R V

[Karl Ylvisaker]

Hello again Srikanth R V,

Srikanth said:

what can be done to prevent this.

From your included screenshot I see that you are still using the 1 Mbps PHY, and that you are using a ~50 ms connection interval. Please try this again with the configuration I mention in my previous reply - 2 Mbps, 7.5 ms connection interval.
This will speed up the communication between the devices, so that the service discovery will take shorter time to complete.
Additionally, if you are worried about the increased power consumption of this low connection interval, you can change the connection interval length after having finished the service discovery. 

Srikanth said:

please find the attached image

For future reference, it is best best if you uploaded the full trace file instead of screenshots, and instead detail in text what you would like to highlight. For example, "The behavior can be seen in the exchange starting on packet #, and again following the --- request at packet #". This allows us to see the full picture of the communication, as well as the things you would like to highlight for us.

Please try again with the configurations I mentioned earlier, and see how this improves the time it takes you to complete the service discovery.

Best regards,
Karl