Mitsubishi MELSEC QS Series, Руководство пользователя

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5
- 14 5.2 Program File Structure
5
MEMORIES AND FILES HANDLED BY CPU MODULE
5.2 Program File Structure
A program file consists of a file header, execution program and allocate memory for online
change.
(1) Structure details
The capacity of the program stored in the program memory of the CPU module is the
total of the above three areas.
(a) File header
This area stores the file name, size, creation date, etc.
The file header size ranges from 26 to 35 steps (104 to 140 bytes) depending on
the device setting of the PLC parameter dialog box.
(Default: 34 steps)
(b) Execution program
This area stores the created program.
(c) Allocate memory for online change
This area is used when online change that increases the number of steps is
performed by GX Developer.
When such an online change is performed by GX Developer, the number of
remaining allocate memory for online change is displayed.
1) Default number of allocate memory for online change
The default setting is 500 steps (2000 bytes).
2) Changing the number of allocate memory for online change
The number of allocate memory for online change can be changed by GX
Developer (by choosing [Online] [Write to PLC] <Program>‚ tab).
When the number of steps is insufficient for online change, it can be set again.
(
Section 6.14.1)
Diagram 5.9 Program file structure
Program file structure
File header
Execution program
34 steps
500 steps
(dafult)
(dafult)
Allocate memory
for online program
change
Area is secured in file size units.
( )
Section 5.3.4