Technical data

Appendix
27.8 Setting the Operating Behavior
Programming with STEP 7
680 Manual, 05/2010, A5E02789666-01
Which Settings Can Be Made?
The module parameters are divided into parameter blocks. Which parameter blocks are available
on which CPU is explained in the "S7-300 Programmable Controller, Hardware and Installation"
Manual and the "S7-400, M7-400 Programmable Controllers, Module Specifications" Reference
Manual.
Examples of parameter blocks:
• Startup behavior
• Cycle
• MPI
• Diagnostics
• Retentive data
• Clock memory
• Interrupt handling
• Onboard I/Os (only for the S7-300)
• Protection level
• Local data
• Real-time clock
• Asynchronous errors
Parameter Assignment with SFCs
In addition to assigning parameters with STEP 7, you can also include system functions in the S7
program to modify module parameters. The following table shows which SFCs transfer which
module parameters.
SFC Purpose
SFC55 WR_PARM Transfers the modifiable parameters (data record 1) to the addressed signal
module
SFC56 WR_DPARM Transfers the parameters from the corresponding SDBs to the addressed signal
module
SFC57 PARM_MOD Transfers all parameters from the corresponding SDBs to the addressed signal
module
SFC58 WR_REC Transfers any data record to the addressed signal module
The system functions are described in detail in the "System Software for S7-300 and S7-400,
System and Standard Functions" Reference Manual.
Which module parameters can be modified dynamically is explained in the following manuals:
• "S7-300 Programmable Controller, Hardware and Installation" Manual
• "S7-300, M7-300 Programmable Controllers, Module Specifications" Reference Manual
• "S7-400, M7-400 Programmable Controllers, Module Specifications" Reference Manual