Mitsubishi Q2ACPU User Manual page 220

12. OVERVIEW OF PROCESSING PERFORMED BY THE QnACPU
(b) If the low-speed execution type program is not processed within surplus time of
the constant scan time or within the low-speed program execution time, the
program execution is interrupted and is resumed in the next scan.
POINT
(1) For the index register processing in the case where a scan execution type
program is switched to a low-speed execution type program, refer to the
QnACPU Programming Manual (Fundamentals).
(2) For the index register processing in the case where an interrupt program is
executed during execution of a low-speed execution type program, refer to the
QnACPU Programming Manual (Fundamentals).
(3) Set a proper low-speed program execution time so that the value obtained by
adding it to the scan time is smaller than the set WDT value.
(4) The COM instruction cannot be used in the low-speed program.
(5) When "Constant scan time" and "Low-speed program execution time" are set,
PRG. TIME OVER (Error code: 5010) occurs in the case of (Surplus time of
constant scan)
Execute the low-speed execution type program either in the constant scan
time or in low-speed program execution time.
(Low-speed program execution time)
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