Usage of System Constants - References - SIMATIC AX - AX Hardware Engineering documentation - Hardware Engineering,

Hardware Engineering reference

Portfolio
SIMATIC AX
Product
SIMATIC AX
Software version
3.0.0
Edition
08/2025
Language
English (original)
Package Name
@ax/hw-docs

After compiling a hardware configuration, hwc will generate ST files including Hardware Identifiers (*_HwIdentifiers.st) and IO Addresses (*_IoAddresses.st) for each module inside the folder SystemConstants. The compile has to be executed within a Apax Project. The generated variables inside the files can be used as symbols to address the hardware identifiers and IO addresses of the configured modules in ST code. Special characters of device- or module names will be replaced with "_"-character.

We recommend to copy the variables from the output ST files into the configuration.st inside the src directory of the apax project, as the ST compiler only accepts files under this directory.