0

This month, I attempted applying bluetooth server chat to Raspberry Pi and try connecting it with the EV3 bluetooth channel to send the communication code between two platforms.

I'm using the Bluetooth server chat by using the example Qt Creator 5.11.3 provided me to demonstrate how the Bluetooth to work. Unfortunately, after I try to build the source code.

The Qt Bluetooth became non-functional. by message "qt.bluetooth: Dummy backend running. Qt Bluetooth module is non-functional. Which also lead to "Cannot bind chat server to "00:00:00:00:00:00" I'm currently new to Qt Creator and Raspberry Pi. What should I do?

I googled for the answer and mostly found the people having the same trouble but on the windows which aren't supported right now. I also tried installing these libraries " libbluetooth-dev bluetooth blueman bluez libusb-dev libdbus-1-dev bluez-hcidump bluez-tools" still no hope.

Raspberry Pi 3 Model B+ Qt Creator version: 5.11.3 OS: Raspbian

ChottiwattJ
  • 1
  • 3
  • Hello! How are you building the application: on the Pi itself, or cross-compiled on another OS? Which Qt version is running on the RasPi, and how did it get there (default version, you installed another one, you built one on the Pi itself... etc)? I can confirm that QtBluetooth does work on the Pi, but in my case I built Qt myself for the Pi (cross-compiled on Linux and then uploaded to Pi). I haven't tried it any other way, so can't comment on that. – Maxim Paperno Aug 30 '19 at 18:39
  • Hello! I'm building the application via Qt on Pi itself. My Qt is 5.11.3 which I installed it myself. Do you have any idea? – ChottiwattJ Aug 31 '19 at 06:09
  • Ah you're using the newer Stretch-based Raspbian? (I just saw that includes Qt 5.11.3, a nice update from 5.7 though still a bit dated.. BTW Debian experimental branch has Qt 12.4 available). Did you install [libqt5bluetooth5](https://packages.debian.org/buster/libqt5bluetooth5) ? And perhaps `qtconnectivity5-dev` as well? – Maxim Paperno Aug 31 '19 at 07:20
  • Obviously, I just installed libqt5bluetooth and qtconnectivity5-dev and the error disappear now. But instead, it shows "qt.bluetooth.bluez: Missing CAP_NET_ADMIN permission. Cannot determine weather a found address is of random or public type. You got any thing on this error? – ChottiwattJ Aug 31 '19 at 09:25
  • I believe that means you need root permissions to do a BT LE scan, or add the executable to the list of allowed ones: https://unix.stackexchange.com/questions/96106/bluetooth-le-scan-as-non-root https://forum.qt.io/topic/90030/missing-cap_net_admin-permission-when-executing-app-through-qt-creator – Maxim Paperno Aug 31 '19 at 23:55

1 Answers1

0

Seems like the answer is to make sure libqt5bluetooth5 and qtconnectivity5-dev are installed.

Maxim Paperno
  • 4,485
  • 2
  • 18
  • 22