Ok, thank you. Here is the link to the topic, regarding update BC217 on another board: BC127 DFU from Embedded CPU
What I would actually like to achieve is a more stable Bluetooth connection through the firmware update. The problem is that in combination with some Bluetooth headsets, the range between BC217 and headset is very low, before it comes to packet loss.
My suspicion is that the headset and BC217 agree on some kind of “low energy standard” when pairing.
If no firmware update is possible, another idea would be to somehow manage to increase the range of the ceramic SMD antenna from the BC217. But I am aware that such a thing will not be so easy without reasonable measurement techniques and expertise in antenna technology.
It would be enough for me if the range is increased by 100cm.