Allen-Bradley Micro870 User Manual

Rockwell Automation Publication 2080-UM002K-EN-E - March 2019 145
Use the High-Speed Counter and Programmable Limit Switch Chapter 8
HSC Mode 7 – Quadrature Counter (phased inputs A and B) With External
Reset and Hold
Blank cells = don’t care,  = rising edge,  = falling edge
HSC Mode 8 – Quadrature X4 Counter
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)
 off (0) off (0) off (0) on (1) HSC Accumulator - 1 count
Example3

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.
TIP
Inputs 0…11 are available for use as inputs to other functions regardless of the HSC being used.
HSC Mode 8 Examples
Embedded Input 1(HSC0)
(A)
Embedded Input 1(HSC0)
(B)
Value of CE Bit Accumulator and Counter Action
▲ OFF TRUE Count Up Acc. Value
▲ ON TRUE Count Down Acc. Value
▼ OFF TRUE Count Down Acc. Value
▼ ON TRUE Count Up Acc. Value
OFF ▲ TRUE Count Down Acc. Value
ON ▲ TRUE Count Up Acc. Value
OFF ▼ TRUE Count Up Acc. Value
ON ▼ TRUE Count Down Acc. Value
OFF or ON OFF or ON X Hold Acc. Value
X X FALSE Hold Acc. Value

Allen-Bradley Micro870 Specifications

General

Brand	Allen-Bradley
Model	Micro870
Category	Controller
Language	English