Panasonic KX-TD816 Features Manual page 110

General Features
• When pressing the doorphone 2 button,
— A doorphone call occurs.
— The extension can answer the doorphone call, but cannot have a conversation.
— The extension can unlock a door by pressing "5".
Connection References
• 2.4.9 Doorphone and Door Opener Connection
Programming Guide References
• [100] Flexible Numbering
• [607-608] Doorphone Ringing Assignment —— Day / Night
• [818] Doorphone Tone Frequency Selection
• [820] Doorphone Ringing Time
• [990] System Additional Information
Features Guide References
• Door Opener
User Manual References
• 4.3.39 Doorphone Call
110 Features Guide