Program File Structure - Mitsubishi 00JCPU User Manual

5.3 Program File Structure

A program file consists of a file header, execution program, and reserved area for online change.
(1) Details of each structure
The capacity of the programs stored in the CPU module program memory is the total of above three areas.
(a) File header
This area stores the name, size, and created date of files.
The file header size ranges from 25 to 35 steps (100 to 140 bytes) depending on the setting made in the Device
tab of the PLC parameter dialog box (34 steps is set by default).
(b) Execution program
This area stores the created program.
(c) R
eserved area for online change
This area is used when the number of steps is increased after writing data in the RUN status from GX
Developer.
When such operation is performed, the remaining reserved area for online change is shown.
1) Default
500 steps (2000 bytes) is set by default.
2) Setting change
To change the number of steps, select [Online]
This setting can be made when data are written in the RUN status. (
5 - 41
Program file structure
34 steps
File header
(By default)
Execution program
Reserved area for
500 steps
online change
Figure 5.38 Program file structure
These areas are reserved in units
Section 5.4.4
of file sizes. (
[Write to PLC] <<Program>> tab in GX Developer.
Section 6.12.1)
)