Omron Sysmac WS02-CXPC1-EV3, Руководство по эксплуатации

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PART 1: CX-Programmer
CHAPTER 5 – Advanced Topics OMRON
CX-Programmer _Page 84
Note: It is possible to have a blank address in this format, in which case the address will be
automatically-allocated by CX-Programmer.
Spreadsheets
When using a spreadsheet to create the data, use a table of the relevant number of columns and rows in the
format above. Ensure that the host application is set to produce tabbed text when pasting (this maybe the
default).
Rules for Symbol Linking / Unlinking
Order of Precedence
Whenever an operation is performed that requires a symbol to be linked or re-linked there is an order of
precedence that the symbol tables are searched in. The order of precedence of searching is as follows,
♦
Search in the local symbol table.
♦
Search in the global symbol table.
Note: Where symbols within the same table have the same address then the Symbol used will be
determined by Alphanumeric order.
Inserting Symbols
When a new symbol is added to a symbol table the ladder diagrams will be searched, looking for an address or
symbol name to match using the order of precedence specified above.
When a new symbol is created without an address and Auto Allocation has been enabled then a new address is
allocated to the symbol. If however Auto Allocation has not been enabled then the symbol’s address is shown
as N/A [Auto] and any operand that uses that symbol will be in error.
Modification of symbols
A symbol may be renamed in the symbol table. Following this the change in name is reflected to the ladder
diagram for any operands that are linked to that symbol. Note that no change in the linkage occurs.
A symbol may have its address modified in the symbol table. Any operands linked to this symbol will remain
linked, however if there are ladder elements with physical addresses which match the symbols new address
these will now be linked to the symbol.
Deleting Symbols
When a symbol is deleted from the symbol table any operands that are currently linked to that symbol will be re-
linked to new symbols. The symbols are searched for using the order of precedence rule. If a new match is
found then the operand will be linked to the new symbol. If however no new match is found then the operand
reverts to the physical address of the deleted symbol.
Entering Contact or Coils into Ladder Diagrams
When a contact or coil is entered into a ladder diagram the user may enter an address, or symbol name.
If an address is entered then the address is searched for in the symbol tables in the order of precedence. If a
symbol with the address is found then it is linked to the contact. If an address is not found then the contact has a
physical address.
If the user enters a symbol name then the symbol tables are searched in order and if a symbol is found with the
same name the contact is linked to that symbol. If no match is found in the symbol tables then a new symbol is
created in the local symbol table and the contact is linked to the new symbol. A new symbol is not created for
instruction operands, as it is not known what data type to create.
If an operand is linked to a symbol in the global symbol table, this link may be overridden by creating a new
symbol in the local symbol table with either the same name or the same address. The operand will then be
linked to the local symbol.
Converting Programs between PLC Types
It is possible to automatically convert a program written for one type of PLC into another. CX-Programmer
attempts to change addresses and mnemonic instructions from the source PLC type to equivalent addresses and
instructions on the new type of PLC.