Mitsubishi 00JCPU, Руководство пользователя

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CHAPTER9 DEVICES
9
9.7 F
ile Register (
R
)
9.7.6 Pr
eca
utions for
using the
file register
9.7.6 Precautions for using the file register
(1) When using the Basic model QCPU
Even if data are written to or read from the file register area whose number is equal to 64K points or more, no
error will occur.
Note that, however, unreliable data may be stored in this kind of reading from the file register.
File register files (MAIN and QDR) cannot be deleted.
However, the contents of the file register can be deleted. (
Section 9.7(3))
(2) When using the High Performance model QCPU, Process CPU, or Redundant
CPU
(a) No registration or use of an invalid file register number
1) When the file of the file register has not been registered
No error will occur even if data are written to or read from the file register.
However, reading data from the file register will result in the following:
• For the standard RAM, unreliable data are stored.
• For a memory card, "0
H
" is stored.
2) When writing to or reading from the file register exceeding the registered size
(points)
No error will occur even if data are written to or read from the file register.
However, reading data from the file register will result in the following:
• For the standard RAM, unreliable data are stored.
• For a memory card, "0
H
" is stored.
(b) File register size check
When writing to or reading from the file register, check the file register size so that data can be written or read
within the size (points) set for the CPU module.
1) Checking the file register size
The file register size can be checked in the File register capacity area (SD647).
*1
The file register size data in units of 1K points is stored in this SD647.
*1: If a file register file is switched to another, the size of the currently selected file register file is stored in SD647.
The remainder after dividing the file register size by 1K points is discarded.
To ensure an accurate "range of use" check, specify the file register setting in units of 1K points (1024 points).