Mitsubishi Q00JCPU User Manual page 249

6
FUNCTIONS
(4) Waiting time from when END processing is executed until next scan
Basic Redundant
Note6.2
Basic
Note6.2
(5) Constant scan accuracy
Basic Redundant
Note6.2
Basic
Note6.2
Note2
Basic
Redundant
Since the Basic model QCPU cannot use low speed execution type programs and fixed scan
execution type programs, it is not necessary to be conscious of this description.
Note6.2
Since the Redundant CPU cannot use low speed execution type programs, it is not necessary to
be conscious of this description.
starts
Sequence program processing is stopped during the waiting time from when the END
processing of a sequence program is executed until the next scan starts.
(a) When low speed execution type program is executed
When a low speed execution type program is being executed, the execution of the
low speed execution type program is stopped for the following period.
(Constant scan) - 0.5ms
(b) When interrupt factor occurs during waiting time until next scan starts
When an interrupt factor occurs during the waiting time until the next scan starts,
either of the following programs is executed.
• Interrupt program
• Fixed scan execution type program
Refer to CHAPTER 10 for the constant scan accuracy.
However, when the program indicated in (a) or (b) below is being executed, the
constant scan may be delayed.
(a) When low speed execution type program is executed
There is a waiting time of 0.5ms when a low speed execution type program is
being executed. (
• When maximum processing time of one instruction is within 0.5ms
The constant scan error is the same as the constant scan accuracy shown in
Section 10.2.
• When maximum processing time of one instruction exceeds 0.5ms
The constant scan time may increase by an excess over 0.5ms.
Also, PRG. TIME OVER (error code: 5010) is detected.
Refer to the following manual for the maximum processing time of one instruction.
QCPU (Q Mode)/QnACPU Programming Manual (Common
Instructions)
(b) When interrupt program/fixed scan execution type program is
Note6.2
executed
Interrupt is enabled while an interrupt program/fixed scan execution type program
is executed. If constant scan time runs out when an interrupt program/fixed scan
execution type program is executed, constant scan cannot be finished. When an
interrupt program/fixed scan execution type program is used, constant scan time
could be shifted by the execution time of an interrupt program/fixed scan
execution type program.
Note6.2
Diagram 3.30,Diagram 3.31)
Note6.2
Note2
Note6.2
6.2 Constant scan
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