The design enables full duplex RS-485 communications over a single pair of conductors rather than four by utilizing bus contention. By adding small-valued serial resistors to the bus lines to limit currents, a tri-stated differential bus is allowed and the SN65HVD96 SymPol transciver can be used to detect a state of bus contention. Simple digital logic and analog filtering techniques enable both transceivers to drive and receive from eachother simultaneously without the need for 2 additional bus wires.
- Full duplex differential signaling
- Up to 1Mbps data rate
- Requires only two bus wires
- Physical level implementation