The ADM3491 datasheet figure 33 shows the the application circuit for full
RS485, is it correct to place a resistor Rt between Y and Z ? Usually I would
place a Rt on the receiver side not on transmitter side.
In a full duplex configuration only the master receiver and most remote slave
receiver need to be terminated. Please see Figure 4 in the attached RS-485/422
Circuit Implementation Guide AN-960.