Reducing connection time when configured as a BLE 5 peripheral to an iOS device

[Spinnaker Design]

We have a prototype device that disconnects and reconnects frequently.  When moving from a BLE 4.2 chip to the nrf52840 (BLE 5), we noticed that the time to complete the initial connection went from about 300ms on the iOS side to about 800ms.  Due to the nature of how the device works, this is a real problem for us.  We tracked the issue down to the additional connection configuration that seems to occur when connecting to a BLE 5 device vs a BLE 4.2 device.  I have attached two screenshots from Wireshark which show the issue.

Is there a way to configure the BLE peripheral device where it will not require as many back and forth commands between the iOS central and our nerf52840 based peripheral device?

 

[Joakim Jakobsen]

Hi.

You mention changing to a BLE 5 chip. Do this only happen when enabling any BLE 5 features?

Br,
Joakim

[Spinnaker Design]

It is mostly tied to the various additional requests BLE 5 needs to complete the connection, such as the FEATURE_REQ.  Since the device on the other end is an iOS device, we don't have a ton of control over that sequence.

[Joakim Jakobsen]

Hi again.

Sorry about the delay here.

Have you made any progress on this, or do you still need assistance?

Br,
Joakim