Rockwell Automation 1794-ID2 U.MNL INCREMENTAL ENCODER - Manual (Page 17)

1–5 Overview of the Incremental Encoder Module
Publication 1794ĆUM015B-EN-P - May 2001
Up/Down Counting Controlled by B Input
Pulse Counting (Mode 000)
1 2 3 2 1
The positive edge of the pulses are counted at input A. If input B = 0,
the counter counts up; if B = 1, th e counter counts down.
Input A
Input B 0
Counter Mode = 0
Counter Register
Logic
A
B = 0/1
Counter Value
Counting Up Counting Down
Up/Down
Up/Down counting controlled by input B
Up/Down Counting using Pulses at Inputs A and B
1 0 2 1
The counter counts up on the positive edge of the pulses at input A,
and counts down on the positive edge of input B.
Input A
Input B 0
Counter Mode = 4
Counter Register
Logic
A
B
Counter Value
Up/Down
1
Up/Down Counting using pulses at the inputs of A and B Pulse Counting Mode (100)