Siemens Simatic S7-300 Technical Data Manual page 86

Cycle and reaction times
5.2 Cycle time
Extending the cycle time
Always make allowances for the extension of the cycle time of a user program due to:
• Time-based interrupt processing
• Process interrupt processing
• Diagnostics and error processing
• Communication with PGs, Operator Panels (OPs) and connected CPs (for example,
• Testing and commissioning such as, e.g. status/controlling of variables or block status
• Transfer and deletion of blocks, compressing user program memory
• Write/read access to the MMC, using SFC 82 to 84 in the user program
• Ethernet communication via integrated PROFINET interface
• CBA communication via PROFINET interface (system load, SFC call, update at scan
• PROFINET IO communication via PROFINET interface (system load)
5-4
Ethernet, PROFIBUS DP)
functions.
cycle check point)
CPU 31xC and CPU 31x, Technical data
Manual, Edition 08/2004, A5E00105475-05