Typical Rs-485 Two-Wire Half Duplex Interface Circuit; Figure - Octagon Systems XE–700 Reference Manual

Figure 4–4 Typical RS–485 two–wire half duplex interface circuit
DE
TX +
Xmitter
DI
TX –
RE
Receiver RX +
RO
46
110 Ω
110 Ω
RX –
Receiver
Xmitter
DE DI
RE
RO
110 Ω
110 Ω
Receiver
Xmitter
DI
DE RE RO
RE
RX
Receiver
RO
DE
RX
TX +
DI
Xmitter
TX