Rockwell Automation Allen-Bradley Micro820

192 Rockwell Automation Publication 2080-UM002M-EN-E - April 2022
Chapter 9 Use the High-Speed Counter and Programmable Limit Switch
Figure 16 - Quadrature Encoder Connected to Inputs
HSC Mode 6 – Quadrature Counter – Phased Inputs A and B
HSC Mode 7 – Quadrature Counter – Phased Inputs A and B with External Reset and Hold
Quadrature Encoder
A
B
Input 0
Input 1
Reverse Rotation
Forward Rotation
B
A
1
2
3
2
1
Count
Input 0
Input 1
Input 2
A
B
Z
Reset
Table 36 - HSC Mode 6 Examples
Input Terminals Embedded Input 0 Embedded Input 1 Embedded Input 2 Embedded Input 3 CE Bit Comments
Function Count A Count B Not Used Not Used
Example 1
(1)
 off (0) on (1) HSC Accumulator + 1 count
Example 2
(2)
ß off (0) on (1) HSC Accumulator - 1 count
Example3 off (0) Hold accumulator value
Example 4 on (1) Hold accumulator value
Example 5 on (1) Hold accumulator value
Example 6 off (0) Hold accumulator value
(1) Count input A leads count input B.
(2) Count input B leads count input A.
Blank cells = don’t care,
 = rising edge,  = falling edge
Inputs 0…11 are available for use as inputs to other functions regardless of the HSC being used.
Table 37 - HSC Mode 7 Examples
Input Terminals Embedded Input 0 Embedded Input 1 Embedded Input 2 Embedded Input 3 CE Bit Comments
Function Count A Count B Z reset Hold
Example 1
(1)

off (0) off (0) on (1) HSC Accumulator + 1 count
Example 2
(2)
ß off (0) off (0) off (0) on (1) HSC Accumulator - 1 count
Example3 ß off (0) off (0) on (1) Reset accumulator to zero
Example 4 on (1) Hold accumulator value
Example 5 on (1) Hold accumulator value
Example 6 off (0) on (1) Hold accumulator value
Example 7 off (0) off (0) Hold accumulator value
(1) Count input A leads count input B.
(2) Count input B leads count input A. Blank cells = don’t care,
= rising edge, = falling edge
Inputs 0…11 are available for use as inputs to other functions regardless of the HSC being used.