Hello,
i have this issue, with those both Librarys, they wont work together. <TFT_eSPI.h> and <ArduinoBLE.h> the error message is: “ undefined reference to HCITransport'"
I was recommended to use the bluefruit.h library, but i am not finding this anywhere..
Glad for any Help, thanks
Hi there,
So, a couple things here.
ONE, You seem to be mixing two things that are not compatible.
Start with, Which BSP are you using? it’s not the right one is more or less what that error indicates, not what it tells you. that’s another thing entirely “undefined reference to HCITransport'”
Two, bluefruit.h is not usually a standalone Library Manager install. It comes from Adafruit’s nRF52 board support package, in the Bluefruit52Lib library inside the Adafruit nRF52 Arduino core.
I have no less than 10 demo video’s of those LIB’s working quite well together on the round display and on the Xiao Dev board with the OLED display. The code is there with each one as well. You will note in the headers’ we try and call out which BSP is used and works. They are supplied by the vendor of the Silicon. and therefore are not always 100% backward compatible with 3rd party Libs , so often you would need to ROLL-BACK the BSP version to allow it to compile.
TFT-eSPI.h has been refactored to work with the current BSP’s but you must still have it configured correctly for your display and driver.
Arduino BLE is Very robust and Just works, when the proper BSP is used.
I can have multiple BLE concurrent connections and notifications 3 & 6 respectively,
2 as minimum without any issues and 4 notifies, go Check out the Thread with Multiple concurrent BLE connects with the Round display on here.
also you can post your code , use the code tags above “</>” paste it in there.
Others can look and you will get better quality help.
GL
HTH 
PJ 