How do you encode door entry units art. 7509 - Tab series - setting the primary and secondary identifier?

Encoding the main ID code: 1_ Lift the handset and press the Bell and Self-start buttons, holding them down until the Bell button starts to flash. 2_ Release the buttons. 3_ Within 5 seconds from release, press the Lock button and hold down until a warning beep is given from the indoor station, and communication between this and the external electronic unit has been established. 4_ Release the Lock button. 5_ Press the button (which?) or type in the code you wish to assign into the entrance panel.  Encoding the secondary ID code: Lift the handset and press the Bell and Self-start buttons, holding them down until the Bell button starts to flash. 2_ Release the buttons. 3_ Within 5 seconds from release, press the Lock and Self-start buttons and hold down until a warning beep is given from the indoor station, and communication between this and the external electronic unit has been established. 4_ Release the Lock and Self-start buttons. 5_ Press the button (which?) or type in the code you wish to assign into the entrance panel.