IFM AC1421 - Access Input and Output Data

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ifm Programming Manual AS-i Gateway AC14 (4.2.x) 12/2017
Programming Access input and output data
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7.3 Access input and output data
Options to access input and output data ................................................................................................27
Validity of the interface data ...................................................................................................................28
Process data of the AS-i slaves .............................................................................................................29
Fieldbus data ..........................................................................................................................................31
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► Familiarise yourself with the following CODESYS functions!
 Addresses according to IEC standard 61131-3:
→ Online help > CODESYS Development System > Programming Reference >
Operanden > Addresses
 Access to IEC address via AT declaration:
→ Online help > CODESYS Development System > Programming Reference >
Declaration > AT Declaration
 Definition of an ALIAS for an IEC address:
→ Online help > CODESYS Development System > Programming Reference > Data
Types > References
 Coupling of a program variable to an address (mapping):
→ Online help > CODESYS Development System > Configuring I/O Links
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7.3.1 Options to access input and output data
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In a CODESYS project, each input and output has a physical address according to the IEC standard
(e.g. %IW5). CODESYS offers the following options to access this address from a PLC application and
thereby to access the input and outputs data of the device:
 Direct access to IEC address
 Access to IEC address via AT declaration
 Definition of an ALIAS for an IEC address
 Link a program variable to an IEC address (mapping)