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Instance DB
S7-GRAPH for S7 300/400 Programming Sequential Control Systems
15-4
C79000-G7076-C526-01
15.7
Structure of an Instance DB
The structure of the instance DB depends on the settings you make in the
"Compile / Save" tab page (menu command Options > Block Settings ). The
following factors affect the content and the size.
•
The parameter set selected for the FB
•
The interface description for the data of steps and transitions (structure
arrays/individual structures). The data are entered automatically.
•
The option of entering criteria analysis data.
•
Number and size of user-defined variables
15.8
Outline of the Structure of the Instance DB
The following table illustrates the divisions within the instance DB.
Area
Identifier
Length
FB parameters
Names of the input and output
parameters of the S7-Graph FB
Depends on the selected parameter set:
2 bytes: minimum
10 bytes: Standard/Maximum
Individual: Maximum V5/User-def.
Reserved work area
G7T_0
16 bytes
Transitions
Transition name (for example
Trans1, Trans2)
(number of transitions) * 16 bytes
Reserved work area
G7S_0
32 bytes
Steps
Step name (for example Step1,
Step2)
(number of steps) * 32 bytes
Sequencer status
-
-
Internal work area
-
-
15.9
FB parameters
The FB parameters are located in the instance DB. The space required by the FB
parameters depends on the setting (minimum, standard, maximum or user-defined
parameter set) made in the "Compile / Save" tab page selected with the menu
command Options > Block Settings . (If, for example, the minimum parameter set
is selected, INIT_SQ is the only parameter displayed).
The following table shows the maximum parameter set V5 (definable).