Mitsubishi MELSEC Q Series Programming Manual page 497

Correct operation example
The following example shows the operation performed when D0 is specified for FD0 in the
subroutine program and D4 is used in the subroutine program.
[Program example]
[MAIN]
[ABC]
[Operation performed after subroutine program execution]
Before the execution
of subroutine program
D0 0
D1 10
D2 100
Transfer
D3 1000
D4 0
Indefinite
Indefinite
FD0
Indefinite
Indefinite
*1: Stores the execution result of the subroutine program.
*2: Replaced by the value of the function device.
(7) The numbers of the devices designated by the arguments in the ECALL(P) instruction
should not overlap. If they do overlap, it will not be possible to obtain accurate calculations.
(8) Up to 16 levels of nesting can be used with the ECALL(P) instruction. However, this 16
levels is the total number of levels in the CALL(P), FCALL(P), ECALL(P), EFCALL(P), and
XCALL instructions.
ECALL "ABC" P0
FEND
END
(9) Devices which are turned ON within subroutine programs will be latched even if the
subroutine program is not executed. Devices turned ON during the execution of a
subroutine program can be turned OFF by the EFCALL(P) instruction.
Immediately after the
execution of ECALL
subroutine program
instruction
D0 0
D1 10
D2 100
D3 1000
0
D4
0
10
FD0 FD0
100
1000
P0
ECALL "DEF" P10
RET
At the time of
execution
D0 0 D0
D1 10 D1
Transfer
D2 100 D2
D3 1000 D3
D4 100 *1 D4
33 *1
1 *1
FD0
100
1000
P10 P20
ECALL "GHI" P20
RET RET
ECALL(P)
1
2
3
4
6
6
7
After the execution of
8
RET instruction
33 *2
1 *2
100 *2
1000 *2
100
Indefinite
Indefinite
Indefinite
Indefinite
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