BLE Version compatibility

[Rakesh R]

Hi All,

I am Working on nRF52840 and using nRF52840-DK.

Below is my working environment

SDK - nRF5_SDK_16.0.0_98a08e2

IDE - Segger Embedded studio (windows 10 - 64 Bit)

Softdevice - s140_nrf52_7.0.1_softdevice

I am having the below queries

1) As I am using softdevice s140 and DFU example, I am able to perform buttonless OTA, but when I am trying to do OTA with the mobile phone having BLE 4.1 I am not able to do.

2) is there any compatibility issue if my device running on BLE 5.0 and trying to connect and communicate with the mobile phones having BLE 4.1 or 4.2?

3) How can I know if my device is running on which BLE version?

[Hung Bui]

Hi Rakesh, 
I would suggest to use a sniffer to check what caused the issue when you use mobile phone with BLE4.1 to do update. Then we can see what we can do. Download the sniffer here: www.nordicsemi.com/.../nRF-Sniffer

You should also check the log on the bootloader to show what's the issue is. 
Please give more description on how you did you test and what happened when you are not able to do DFU.