2022-11-16 04:59 AM
I'm playing with the above mentioned example using the WB55 nucleo board.
When using a Samsung S10 on android with BLE Toolbox from STMicro we can reach 100-160kbyte/s throughput.
When using a HP notebook with builtin or TPLink/ASUS bluetooth dongle the datarate is much less 30-60kbyte/s
Using a BLE Sniffer from nordic we captured the BLE traffic and see that the difference is that sometimes the PC/usb dongle hops to a channel the master sends the empty pdu but no answer from the slave (STM32WB55) happens, thus at least one connection interval of data transfer is missed.
I believe here at least an "empty pdu" should be answered by the lower level of the STM32 BLE Stack. What could be the reason for such a difference?
In both case the phone/dongle were in close proximity (5-10cm), in both case the negotiated interval was 48.75ms.
The above was observed with 1M PHY configuration. I was not able to reproduce it with the 2M PHY.
sidenote: on the above screenshot the hop sequence is 23->36->12->33->1 for some reason channel 12 was missing thus the 97ms time difference comapred to the channel 36 empty PDU
2022-11-16 05:01 AM
Just found somewhat similar occasions for the 2M PHY.