Hello, Long story short, I am trying to connect with a linux PC using a Bluetooth 5 universal adapter (Asus USB-BT500) to a Bluetooth 5 module PCB, called BT832X which is using a Bluetooth Low Energy Technology that is using a chip Nordic nRF52832 (see url for the module documentation https://static1.squarespace.com/static/561459a2e4b0b39f5cefa12e/t/63de8b578e4d7813cde64445/1675529048975/BT832X-p+Product+Specifications.pdf). Therefore I tried everything, reading docs, sniffing through the bluetoothctl sources, gatttools sources, and I am not able to open and connect on a socket on my PC to connect properly. Usually for legacy Bluetooth stuff, I create a RF_COMM socket, and the magic is done by itself. No biggie. Here I tried an L2CAP approach (not sure if I had a proper configuration), I tried to use the gatttool as it is, without success. I feel a bit lost. The remote device is working properly, because using the Nordic demo Android app (downloadable from Google Play Store), I am able to communicate with the PCB and exchange packages. Do you have a functional, very simple sample, or suggestion, preferably in C, to help me to open a socket and send a data package? I mean, you have a BLE module, you want to connect with it using BlueZ, how do you open a socket, how do you configure it, connect to it and send a byte through it? Let's keep in mind that I am already able to scan for the destination address (I created a custom agent in bluetoothctl that is fishing data using the "scan on" command), so the address that I'm connecting to is already known. Thank you and I'm really really looking forward to your reply. Cristian-Stefan