Mitsubishi 00JCPU, User Manual

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CHAPTER2 SEQUENCE PROGRAMS
2
3
2.3 Settings When Progr
am is Divided
2.3.3 L
ow-speed execution typ
e progr
am
(e) Low-speed scan time
Low-speed scan time is a total of the execution time of all low-speed execution type programs and the low-
speed END processing time.
For differences between the low-speed scan time and the scan time, refer to Figure 2.31.
1) Low-speed scan time storage location
The CPU module measures the low-speed scan time and stores it into the special register (SD528 to SD535).
The low-speed scan time can be checked by monitoring SD528 to SD535.
If the stored values in SD528 and SD529 are 50 and 400 respectively, the low-speed scan time is
50.4ms.
Remark
The low-speed scan time and program execution time can be checked on the Program monitor list screen.
(
Section 6.13.1)
2) Accuracy and measurement of low-speed scan time
Accuracy of each low-speed scan time stored in the special register is 0.1ms.
Even if the WDT instruction (instruction that resets the watchdog timer) is executed in a sequence program,
the measurement of each low-speed scan time continues.
3) Execution of an interrupt program or fixed scan execution type program
The execution time of an interrupt program or fixed scan execution type program will be added to the low-
speed scan time.
Figure 2.31 Low speed scan time storage location
Stores the low-speed scan time of 1ms or less (unit: s).
Stores the low-speed scan time. (unit: ms).
Current value SD528 SD529
Minimum value SD532 SD533
Maximum value SD534 SD535
Example