Automatic control function programming manual ladder language

Functions
IMPORT() is used to process an external object in a module.
EXPORT() is used to make an object available to other modules for use.
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! CAUTION
An object cannot be imported until it has been exported by its owner module.
The user defines the imported and exported objects in the main() function of his modules.
When the translator is called, the monitor updates a table of exports and a table of imports. These two tables contain
the lists of symbols and their respective addresses. Once all the main() functions of all the modules have been called,
the monitor can create the links between exported objects and imported objects.
The symbol name is used by the monitor to link objects. The same name can therefore not be used to export two
different objects.
Module A
EXPORT ("NAME",
Addr1)
Monitor
NAME : Symbol (Character string)
This symbol is used during import
Addr1: Address of the object to be exported (defined in module A)
Addr2: Address of the object that will be used in module B
Table of Exports
Symbol @Symb
NAME Addr1
Addr2 = Addr1
Table of Imports
Symbol @Symb
NAME Addr2
Module B
IMPORT ("NAME",
Addr2)