Problem when connecting BLE 4.x device and BLE 5.0 device at same time

[Oliver71]

Need support.

 

I am using lierda S98B module together with Nordic S140 SoftDevice as master. So far everything works fine. I can connect up to 4 devices with BLE 4.2. Also I can connect up to 4 devices with BLE 5.0.

 

But after connecting a BLE 4.x device once no more devices with BLE 5.0 can be connected. If configure BLE_BAS_CONFIG_LOG_LEVEL 4 following debug message can be found:

 

00> <info> app: Start Service Discovery

00> <debug> nrf_ble_gq: Purging request queue with id: 1

00> <debug> nrf_ble_gq: Registering connection handle: 0x0001

00> <debug> ble_db_disc: Starting discovery of service with UUID 0xFFF0 on connection handle 0x1.

00> <debug> nrf_ble_gq: Adding item to the request queue

00> <debug> nrf_ble_gq: GATTC Primary Services Discovery Request

00> <debug> nrf_ble_gq: SD is currently busy. The GATT request procedure will be attempted                       again later.

00> <debug> nrf_ble_gq: Processing the request queue...

00> <debug> nrf_ble_gq: GATTC Primary Service Discovery Request

00> <debug> nrf_ble_gq: SD is currently busy. The GATT request procedure will be attempted                           again later.

00> <debug> nrf_sdh_ble: BLE event: 0x11.

 

Anyone can help ?

[Simonr]

Hi Oliver

From the sniffer traces the disconnection seems to be caused from the transmitter here, as the central only reports that the "remote user terminated connection", so we would need logging from the peripheral devices to see why the disconnect occurs.

I tested this quickly on my end as well with one central, one BLE 4.2 peripheral and one BLE 5.0 peripheral with nRF52 DKs, and did not see this issue on my end. I used the BLE app in nRF Connect for Desktop as the central application here, so you can try that on your end as well with the gen 1 and gen 2 peripherals and see if it's able to connect to both generations if you have a DK available.

Best regards,

Simon