Motorola 68P02958C00-B - Manual (Page 79)

Site Configuration
5-22
Microwave, Full-Duplex, Sync
For full-duplex, synchronous microwave communication, using the Line Modem board.
Microwave, Full-Duplex, Async
For full-duplex, asynchronous microwave communication, using the Line Modem board.
Microwave, Half-Duplex
For half-duplex microwave communication, using the Line Modem board.