IDEC MICROSmart FC6A Series User Manual page 271

Settings
■ Operation mode
For group 1 and group 5, you can select Single-phase High-speed Counter or Two-phase High-speed Counter.
Only Single-phase High-speed Counter can be selected for Group 2, Group 4, and Group 6.
The operation mode that can be selected for Group 3 depends on the type of FC6A Series MICROSmart.
Only Single-phase High-speed Counter can be selected for the All-in-One CPU module. Single-phase High-speed
Counter and Two-phase High-speed Counter can be selected for the Plus CPU module.
■ Counting mode (single-phase high-speed counter)
When the Single-phase High-speed Counter is specified for Operation Mode of Group 1 or Group 5, Counting Mode can
be selected as Adding Counter, Up/Down Selection Reversible Counter, or Dual-Pulse Reversible Counter.
Only Adding Counter can be selected for Group 2, Group 4, and Group 6 high-speed counters.
The counting mode that can be selected for Group 3 depends on the type of FC6A Series MICROSmart.
Only Adding Counter can be selected for the All-in-One CPU module. Adding Counter, Up/Down Selection Reversible
Counter, and Dual-Pulse Reversible Counter can be selected for the Plus CPU module.
Adding counter
The adding counter counts up with the rise in pulse input.
Up/down selection reversible counter
Up/down selection reversible counter can switch between addition and subtraction with the up/down selection input. When the
up/down selection input is on, the counter counts up with the rise in pulse input. When the up/down selection input is off, the
counter counts down with the rise in pulse input.
Dual-pulse reversible counter
This counter switches between the up count and the down count with pulse input (up) and pulse input (down) pulses. When a
pulse is input to pulse input (up), the counter counts up with the rise in the pulse. When a pulse is input to pulse input (down),
the counter counts down with the rise in pulse input.
Note: When Group 1, Group 3 (Plus CPU module), or Group 5 is set to Up/Down Selection Reversible Counter, Dual-Pulse Reversible
Counter, or Two-phase High-speed Counter, Group 2, Group 4, or Group 6 has the same setting.
■ Counting mode (two-phase high-speed counter)
When the two-phase high-speed counter is specified for Operation mode for group 1, group 3 (Plus CPU module), or group 5, the
counting mode can be selected as 2-edge count or 4-edge count.
2-edge count
This counter counts at double the frequency of the input pulse.
This counter counts by the phase difference between the A-phase and B-phase pulse input. When the A-phase precedes the B-
phase, the counter counts up with the rise and fall of the B-phase. When the B-phase precedes the A-phase, the counter counts
down with the rise and fall of the B-phase.
4-edge count
This counter counts at quadruple the frequency of the input pulse.
This counter counts by the phase difference between the A-phase and B-phase pulse input. When the A-phase precedes the B-
phase, the counter counts up with the rise and fall of the A-phase and the B-phase. When the B-phase precedes the A-phase,
the counter counts down with the rise and fall of the A-phase and the B-phase.
■ Comparison action
The comparison action is a function that compares the high-speed counter's current value with a preset value (target value).
It can use either the comparison output or an interrupt program. However, the interrupt program can only be used when ladder
program is selected as the programming language.
When Comparison Output is selected, the specified external output is turned on when the current value and the preset value match.

When Interrupt Program is selected, the subroutine program with the specified label number is executed as the interrupt program when

the current value and the preset value match.
Overflow and underflow can also be used for the comparison conditions.
For details on the comparison actions, see "Comparison Actions" on page 5-21.
FC6A S MICROS U
ERIES MART
' M FC9Y-B1722
SER S ANUAL
5: F S
UNCTIONS AND ETTINGS
5-25