Allen-Bradley MicroLogix 1000 User Manual

Preface
MicroLogix 1000 Programmable Controllers User Manual
12–6
High-Speed Counter (HSC)
Use this instruction to configure the high-speed counter. Only one HSC instruction
can be used in a program. The high-speed counter is not operational until the first
true execution of the HSC instruction. When the HSC rung is false, the high-speed
counter is disabled from counting, but all other HSC features are operational.
The Counter address of the HSC instruction is fixed at C5:0.
After the HSC is configured, the image accumulator (C5:0.ACC) is updated with the
current hardware accumulator value every time the HSC instruction is evaluated as
true or false.
Entering Parameters
Enter the following parameters when programming this instruction:
• Type indicates the counter selected. Refer to page 12–7 for making your
high-speed counter selection. Each type is available with reset and hold
functionality.
• High Preset is the accumulated value that triggers a user-specified action such
as updating outputs or generating a high-speed counter interrupt.
• Accumulator is the number of accumulated counts.
The following terminology is used in the following table to indicate the status of
counting:
• Up↑ – increments by 1 when the input energizes (edge).
• Down↑ – decrements by 1 when the input energizes (edge).
• Reset↑ – resets the accumulator to zero when the input energizes (edge).
• Hold – disables the high-speed counter from counting while the input is
energized (level).
• Count – increments or decrements by 1 when the input energizes (edge).
• Direction – allows up counts when the input is de-ener gized and down counts
while the input is energized (level).
• A – input pulse in an incremental (quadrature) encoder (edge/level).
• B – input pulse in an incremental (quadrature) encoder (edge/level).
• Z – reset pulse in an incremental (quadrature) encoder (edge/level).
• ↑ – the signal is active on the rising edge only (off to on).
Execution Times
(µsec) when:
True False
21.00 21.00
HSC
HIGH SPEED COUNTER
Type
Counter C5:0
High Preset 0
Accum 0
(CD)
(CU)
(DN)
efesotomasyon.com - Allen Bradley,Rockwell,plc,servo,drive

Allen-Bradley MicroLogix 1000 Specifications

General

Brand	Allen-Bradley
Model	MicroLogix 1000
Category	Controller
Language	English