Install services

Run this in a terminal to copy the required files

sudo cp bt_bind*.service /lib/systemd/system

Then to enable/update required services (bluetooth) do the following:

First edit the bluetooth service:

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

Modify/Add the lines below:

ExecStart=/usr/sbin/bluetoothd -C --noplugin=sap
ExecStartPost=/usr/bin/sdptool add SP

Then restart the bluetooth services

sudo systemctl daemon-reload
sudo rfkill block bluetooth
sudo rfkill unblock bluetooth
sudo systemctl stop bluetooth.service
sudo systemctl enable bluetooth.service
sudo systemctl start bluetooth.service
sudo systemctl enable dbus-org.bluez.service
sudo systemctl restart dbus-org.bluez.service

Restart the system sudo reboot

Pair devices

Run the Bluetooth controller:

sudo bluetoothctl

You will see a prompt like this: [bluetooth]#

Copy this commands to enable Bluetooth and start scanning

power on
system-alias ‘Farmerin’
scan on

You will see some new devices, note those that will be connected later. In this case these devices are name0 and name1 (with mac0 and mac1)

...
[NEW] Device <mac0> <name0>
...
[NEW] Device <mac1> <name1>
...

Now pair and trust those devices.

pair <mac0>
PIN 0000
trust <mac0>
pair <mac1>
PIN 0000
trust <mac1>

Once finished stop the scanner

scan off

Now exit the controller with CTRL+D

Bind devices to rfcommX

# To enable binding of device 0 with mac0
sudo systemctl enable bt_bind0@<mac0>.service
sudo systemctl start bt_bind0@<mac0>.service

# To enable binding of device 1 with mac1
sudo systemctl enable bt_bind0@<mac0>.service
sudo systemctl start bt_bind1@<mac1>.service

You should see the binded devices as /dev/rfcommX:

ls /dev/rfcomm*

Now you can open a serial terminal and test:

picocom -b 9600 /dev/rfcomm0