3.2.5.2 Direction Discriminator Modes 1 to 5

A channel's quadrature signals Ua1 and Ua2 identify forward or backward directions. If Ua1 leads Ua2, the forward direction is indicated and the counter will count up. If Ua1 lags Ua2, the reverse direction is indicated and the counter will count down.

Figure 3-5 Direction Discriminator Modes

The next figures show the five available direction discriminator modes, and the reaction of the encoder circuit to these modes.

Figure 3-6 shows the waveforms which force the encoder circuit to generate pulses for counting up.

Figure 3-6 Direction Discriminator Up Clock

Figure 3-7 shows the waveforms which must be used for counting down.

Figure 3-7 Direction Discriminator Down Clock