An RS-485 bus consists of multiple transceivers connected in parallel to a bus cable. To eliminate line reflections, each cable end is terminated with a termination resistor, R_T, whose value matches the characteristic impedance, Z₀, of the cable. This method, known as parallel termination, allows higher data rates over a longer cable length.

Figure 10-2 Typical RS-485 Network With Half-Duplex Transceivers