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2-2
Section
CPM2A/CPM2C High-speed Counters
45
2-2
CPM2A/CPM2C High-speed Counters
CPM2A CPU Units and most CPM2C CPU Units have five points for high-speed
counters: One point for a high-speed counter with a maximum response fre-
quency of 20 kHz, and four points for interrupt inputs (counter mode).
CPM2C CPU Units with 10 I/O points have four points for high-speed counters:
One point for a high-speed counter with a maximum response frequency of
20 kHz, and three points for interrupt inputs (counter mode).
High-speed
counters
High-speed counter
1 point
No interrupts
Count check
interrupts
Target value com-
parison interrupts
Range comparison
interrupts
No interrupts
Count-up
interrupts
Interrupt inputs
(counter mode)
4 points
(2 points in CPM2C CPU
Units with 10 I/O points
and CPM2C-S CPU Units)
The CPM2A/CPM2C provides both a built-in high-speed counter and built-in in-
terrupt inputs.
High-speed Counter
The built-in high-speed counter is a counter based on inputs to the CPU Unit’s
built-in points 00000 to 00002. The high-speed counter itself has one point, and
it can provide either an incrementing/decrementing or just an incrementing
count depending on the mode setting.
Input No.
(See note.)
Response
frequency
Input mode (count value)
Control method
00000
00001
5 kHz
Differential phase input mode
(-8388608 to 8388607)
Target value
comparison interrupts
0000
00002
20 kHz
Pulse + direction input
mode(-8388608 to 8388607)
Up/down pulse input mode
(-8388608 to 8388607)
Increment mode
(0 to 16777215)
co pa so
e up s
Range comparison
interrupts
Note
Input points not used for counter inputs can be used as ordinary inputs.
Interrupt Inputs (Counter Mode)
Interrupt inputs (counter mode) are counters based on inputs to the CPU Unit’s
built-in points 00003 to 00006 (00003 to 00004 in CPM2C CPU Units with 10 I/O
points and in CPM2C-S CPU Units). These counters have four points, and they
can provide either an incrementing or decrementing count depending on the
mode setting. Since this function utilizes interrupt inputs for counting, it is not
possible to use the same inputs for other interrupt inputs.
Input No.
(See note.)
Response
frequency
Input mode (count value)
Control method
00003
2 kHz
Incrementing counter
(0000
FFFF)
Count-up interrupts
00004
g
(0000 to FFFF)
p
p
00005
Decrementing counter
(0000 to FFFF)
00006
(0000 to FFFF)
Note
1. Input points not used for counter inputs can be used as ordinary inputs.
Types of High-speed
Counters