8.3.1.2 Active Polarity Definition by the Master Node

THVD1505 polarity correction can also work without a fail-safe resistor network. See Figure 20.

Figure 20. Active Polarity Definition

In this scenario, the master node drives the bus for longer than t_FS. After a time, t > t_FS, the master begins transmitting data. Figure 21 shows the timing diagram for active polarity definition. DIR pin refers to the output of the MCU that is driving DE and RE pins in Figure 21.

Figure 21. Polarity Correction Timing With Active Polarity Definition

POLCOR logic behavior with active polarity definition is identical to the POLCOR logic behavior with passive polarity definition.