2-Wire Line, Point-To-Point; 2-Wire Line, Multi-Drop - semaphore KINGFISHER PLUS+ Hardware Reference Manual

Kingfisher Plus+ Hardware Manual

6.8.3 2-Wire Line, point-to-point

Either RTU can transmit/receive one at a time.
Note: line termination is required.

6.8.4 2-Wire Line, multi-drop

Any RTU can transmit/receive one at a time.
Note: line termination is required.
Hardware Manual Version 7.16 http://www.servelec-semaphore.com/ Page 109