Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers - Manual (Page 224)

Preface MicroLogix 1000 Programmable Controllers User Manual
12–10
Up Counter with Reset and Hold
Input state
H g -Speed
Input Count
(I/O)
Input
Direction
(I/1)
Input Reset
(I/2)
Input Hold
(I/3)
HSC Rung
High-Speed
Counter Action
Turning
Off-to-On
NA
Off, On, or
Turning Off
Off True Count Up
NA NA
Off, On, or
Turning Off
On NA Hold Count
NA NA
Off, On, or
Turning Off
NA False Hold Count
Off, On, or
Turning Off
NA
Off, On, or
Turning Off
NA NA Hold Count
NA NA Turning On NA NA Reset to 0
NA (Not Applicable)
Using the Bidirectional Counter and the Bidirectional Counter with Reset
and Hold
Bidirectional counters are used when the parameter being measured can either
increment or decrement. For example, a package entering and leaving a storage bin
is counted to regulate flow through the area.
The Bidirectional Counters operate identically except for the operation of inputs 1
and 0. For the Pulse and Direction type, input 0 provides the pulse and input 1
provides the direction. For the Up and Down type, input 0 provides the Up count
and input 1 provides the Down count. Both types are available with and without
reset and hold. Refer to page 12–7 for more information regarding Bidirectional
Counter types.
For the Bidirectional Counters, both high and low presets are used. The low preset
value must be less than the high preset value or an error
INVALID PRESETs
LOADED TO HIGH SPEED COUNTER (37H) occurs.
Bidirectional Counters operate in the –32,768 to
+
32,767 range inclusive and can be
reset to zero using the Reset (RES) instruction.