Bluetooth UART

Step 1. Add the Serial Port Profile on the Pi

sudo nano /etc/systemd/system/dbus-org.bluez.service

Add the compatibility flag, ' -C', at the end of the 'ExecStart=' line. Add a new line after that to add the SP profile. The two lines should look like this:

ExecStart=/usr/lib/bluetooth/bluetoothd -C
ExecStartPost=/usr/bin/sdptool add SP

Save the file and reboot.

Step 2. Pair and trust the DLC32

bluetoothctl
scan on

You'll see a number of Bluetooth device addresses; one should be labeled as your device. If your device needs to be put into 'discoverable' mode, read the manual and do that first.

pair <bdaddr>
trust <bdaddr>

You can now 'exit' from bluetoothctl.

Step 3. Build rfcomm service

sudo nano /etc/systemd/system/rfcomm.service

Enter the following:

[Unit]
Description=RFCOMM service
After=bluetooth.service
Requires=bluetooth.service

[Service]
ExecStart=/usr/bin/rfcomm bind hci0 <bdaddr>

[Install]
WantedBy=multi-user.target

Enable that to start at boot time with:

sudo systemctl enable rfcomm

Reboot the pi:

sudo reboot

Connect to DuneWeaver webgui and verify rfcomm serial port visible and connects.

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