IDEC SmartAXIS Touch FT1A Series, Руководство пользователя

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SmartAXIS Touch User's Manual
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4 Special Functions
3
Pr
oject
4.7 High-Speed Counter
This section describes the high-speed counter for counting high-speed pulses from devices such as rotary encoders
and proximity switches.
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Feature Description
The high-speed counter is a function that counts high-speed pulses which cannot be read in the execution of a normal
ladder program or FBD program. The high-speed counter has a comparator function to compare the current value
and a preset value (target value). When the current value and the preset value match, an external output is turned on
or an interrupt program is executed. However, the interrupt program can only be used when ladder program is
selected as the programming language.
The high-speed counter has a single-phase high-speed counter and a two-phase high-speed counter.
To use the high-speed counter, function area settings, data registers, special internal relays, and special data
registers must be configured.
To use the high-speed counter, the following settings are required.
Application example
This application example punches holes into a roll of paper at a regular interval.
The two pulses (A-phase, B-phase) that carry the phase difference output from the rotary encoder are counted by the
Touch two-phase high-speed counter.
When the current value reaches the preset value, the specified external output turns on and the perforator punches a
hole in the roll of paper.
High-speed counter operation modes
The high-speed counter has the following two operation modes.
• Single-phase high-speed counter
• Two-phase high-speed counter
High-speed counting modes
The high-speed counter has the following three counting modes.
• Adding counter (single-phase high-speed counter)
• 2-edge count (two-phase high-speed counter)
• 4-edge count (two-phase high-speed counter)
Example: The input allocation when external input group 1 is specified as a two-phase high-speed counter
Ladder program: WindLDR function area settings and settings for data registers, special internal relays, and
special data registers
FBD program: WindLDR function area settings and high-speed counter function block (HSC FB) settings
For details on the HSC FB, refer to Chapter 18 "The special FB" - "HSC (High-speed Counter)" in
the "SmartAXIS FBD Programming Manual".
Paper roll
Paper feed roller
Perforator
Rotary
encoder
Two-phase pulses
High-speed pulse input
Output when count matches
SmartAXIS
Pulse motor
External input I0 I1 I2
↓ ↓ ↓
High-speed counter A-phase B-phase External clear input (Z-phase)