Mitsubishi 00JCPU User Manual page 413

(4) Interrupt counter
(a) Definition
The interrupt counter counts how many times an interrupt factor has occurred.
(b) Count processing
1) When an interrupt occurs
The interrupt counter updates its current value when an interrupt occurs.
To utilize the interrupt counter, any program that includes the interrupt counter is not required.
2) Counting of the interrupt counter
The interrupt counter does not stop its counting even if a set value is specified.
To use the interrupt counter for control purposes, use comparison instructions (=, <=, etc.) for comparison
with the set value to turn on or off a device such as the internal relay (M).
For example, to turn on M0 when interrupt input to I0 turned on ten times, create the program as shown in
Figure 9.40. (In this case, "C300" is the interrupt counter corresponding to I0.)
(c) Setting the interrupt counter
Set the "Interrupt counter start No." in the PLC system tab of the PLC parameter dialog box.
The number of points indicated in Table9.5 starting from the set counter number is used as the interrupt
counter.
Basic model QCPU
128 points, starting from the set counter number, are used as the
interrupt counter.
When the Interrupt counter start No. is set to C300, the range of
C300 to C427 is used as the interrupt counter.
C300 I0
C301 I1
C302 I2
Interrupt counter (128 points)
C427 I127
Corresponding interrupt pointer
To use the interrupt counter, enable the interrupt by the EI instruction in the main routine program.
= K10 C300
Figure 9.40 Ladder example of using the interrupt counter for control
Table9.5 Interrupt counter points for each CPU module
M0
High Performance model QCPU, Process CPU, Redundant CPU
256 points, starting from the set counter number, are used as the
interrupt counter.
When the Interrupt counter start No. is set to C300, the range of
C300 to C555 is used as the interrupt counter.
C300 I0
C301 I1
C302 I2
Interrupt counter (256 points)
C555 I255
Corresponding interrupt pointer
CHAPTER9 DEVICES
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