Mitsubishi Electric melsec q00ujcpu User Manual page 63

(b) Changing the program execution type using instructions
Use the PSCAN, PSTOP, or POFF instruction to change a program execution type.
1) Changing the execution type (in the case of scan execution type program)
• Set the programs "ABC" and "GHI" as scan execution type programs and the program "DEF" as a stand-
by type program.
• When the condition is established (the internal relay (M0) in Figure 2.27 turns on), the program "DEF" is
changed to a scan execution type program and the program "ABC" to a stand-by type program.
[Before execution of the PSCAN and PSTOP instructions]
Scan execution type program: ABC
Stand-by type program: DEF
[After execution of the PSCAN and PSTOP instructions]
Stand-by type program: ABC
Scan execution type program: DEF
Figure 2.27 Example of changing the execution type (in the case of scan execution type program)
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MO
PSCAN "DEF"
PSTOP "ABC"
PSCAN "GHI"
PSTOP "DEF"
MO
PSCAN "DEF"
PSTOP "ABC"
PSCAN "GHI"
PSTOP "DEF"
• The PSCAN instruction changes the program "DEF" to
a scan execution type program.
• The PSTOP instruction changes the program "ABC" to
a stand-by type program.
Scan execution type program: GHI
When M0 turns on
Scan execution type program: GHI
PSCAN "ABC"
PSTOP "GHI"
PSCAN "ABC"
PSTOP "GHI"