Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) User Manual
Page 258
Chapter 14
Using High-Speed Counter Instructions
14–8
When a high preset is reached, no counts are lost.
•
Hardware and instruction accumulators are reset.
•
Instruction high preset is loaded to the hardware high preset.
•
If the DN bit is not set, the DN bit is set. The IH bit is also set and the IL,
IV, and IN bits are reset.
•
If the DN bit is already set, the OV bit is set. The IV bit is also set and
the IL, IV and IN bits are reset.
•
High-speed counter interrupt file (file 4) is executed if the interrupt is
enabled.
The following tables summarize what the input state must be for the
corresponding high-speed counter action to occur:
Up Counter
Input State
High-Sp d
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
NA
NA
True
Count Up
NA
NA
NA
NA
False
Hold Count
NA (Not Applicable)
Up Counter with Reset and Hold
Input state
High-Sp d
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)