10 - 54 10 - 54
MELSEC-Q
10 DEVICES
(2) Number of local pointer points
Local pointers can be divided among all the programs stored in the program
memory.
The local pointer No. ranges from P0 to the highest No. of the local pointer in use.
(The High Performance model QCPU's OS computes the number of points used.)
Even if only P99 is used in a program, for example, the number of points used
will be counted as 100 between P0 and P99.
Therefore, when local pointers are used at several programs, the pointer settings
should begin from P0.
If the total number of pointers (total for all programs) exceeds 4096 points, a
pointer configuration error (error code:4020) occurs.
P0 to P99 used in
program
P100 to P199 used
in program
Only P299 is used
in program
P0 to P99 occupy
100 points
P0 to P199 occupy 200 points P0 to P299 occupy 300 points
If P0 is used, the
number of occupied
points is 1.
If P0 to P99 are used,
the number of
occupied points is 100.
Total of 600
points used.
Program A
Program B
Program C
If the local pointer points are used as follows, the total is 600 points.
Example
10.9.2 Common pointers
(1) Definition
(a) Common pointers are used to call sub-routine programs from all programs
being executed in the High Performance model QCPU.
Program A
FEND
CALL P204
Program C
P204
P205
CALL P0
RET
RET
END
Program B
FEND
CALL P205
Label
(b) The same pointer No. cannot be used again as a label.
Such use will result in a pointer configuration error (error code:4021).
Содержание QCPU (Q Mode)
Страница 111: ...5 19 5 19 MELSEC Q 5 ASSIGNMENT OF I O NUMBERS MEMO ...
Страница 450: ...App 59 App 59 MELSEC Q APPENDICES MEMO ...