24
3 PROGRAM ORGANIZATION UNITS
3.3 Function Blocks (FB)
■Capacity of instance
The capacity of each data area of an instance should be calculated as follows.
• Capacity of local label area
Capacity of local label area of instance = Total capacity of data of local labels (except the ones with latch attribute) + Capacity
of reserved area
• Capacity of local latch label area
Capacity of local latch label area of instances = Total capacity of data of local labels with latch attribute + Capacity of reserved
area
• Capacity of signal flow for FB
In the macro type function block, the number of steps are the same as the program.
The capacity of the subroutine type function block is as follows.
Capacity of signal flow for FB (word) = The number of program steps of the function block / 16 + Capacity of reserved area
If the reserved area capacity cannot be allocated to the data to be added by online change, the online change
cannot be executed and all programs are required to be converted (reassigned).
Item Description
Capacity of local labels (except the ones with latch
attribute)
Total capacity of the data used for local labels.
The capacity of areas to be used differs depending on the memory assignment of labels. For details on
memory assignment of labels, refer to the following.
GX Works3 Operating Manual
Capacity of reserved area 48 words.
Item Description
Capacity of latch attribute local labels Total capacity of the data used for latch attribute local labels.
The capacity of areas to be used differs depending on the memory assignment of labels. For details on
memory assignment of labels, refer to the following.
GX Works3 Operating Manual
Capacity of reserved area 16 words.
Item Description
Capacity of signal flow for FB Total capacity of the signal flow for FB for the instruction in the function block definition
Capacity of reserved area 8 words.
To Next Page
Loading...
