nrf52840 slow rx characteristic time

[_maibi]

The nRF52840 has a longer rx characteristic reception time than the nRF51822.

 --> android terminal log

first and second line nRF52840 , It takes almost 1.2 seconds to get the rx characteristic.

below nRF51822, It takes almost 0.4 seconds.

why It happens? What should I do to improve the performance?

NRF52840 -

SDK 15.3.0, with buttonless dfu service

NRF51822 - 

SDK 12.3.0 - w/o buttonless dfu service

Other application layer are almost same.

[Simonr]

Hi

You've used two completely different "connected packets" when measuring the time here.

If you use the same packet, say the CONNECT_REQ packet in both instances, the times will be:

nRF51822_Galaxy_Note_4: 2.227 - 0.8359 = 1.39s

nRF52840_Galaxy_Note_4: 2.392 - 0.8065 = 1.58s

This is a very short time, and can not be counted as a delay. Furthermore, the time we see on the left side of the sniffer log is the time it takes for the computer to see the logs, so to be even more accurate, we should calculate the delta time (µs start to start) for each event to get the exact timing.

Best regards,

Simon

[_maibi]

What is the connection confirm response message for connect request?

As you say, I compare different packets.