Bluetooth PIN

To enable pairing with a PIN code instead of Simple Secure Pairing mode, the following steps are required:

1. Change sspmode 1 to sspmode 0 in /etc/systemd/system/bthelper@.service.d/override.conf
2. Add --pin /etc/bluetooth/pin.conf to the ExecStart line in /etc/systemd/system/bthelper@.service.d/override.conf
3. Add a file /etc/bluetooth/pin.conf which contains PIN code for the devices:

AA:BB:CC:DD:EE:FF 1234 (replace AA:BB:CC:DD:EE:FF with your Bluetooth devices's Mac address or * to use PIN 1234 for all devices)

Notes

• This does not work with iOS devices. iOS refuses to pair with devices that do not support SSP. So sspmode needs to be on
• Even with sspmode=1 and a PIN file, iOS would not connect at all
• macOS allows pairing with devices with sspmode=0 (and a PIN configured on the Pi). When sspmode=1, macOS decides upon a PIN and either the Pi has a fixed PIN list (which does not match => connection refused), or requires keyboard input on the Pi (which is not desired for a headless device).

So you need to try yourself if this works with your setup.