Personal Computer User Manual

Cycle and reaction times
5.2 Cycle time
CPU 31xC and CPU 31x, Technical data
5-4 Manual, Edition 08/2004, A5E00105475-05
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,
Ethernet, PROFIBUS DP)
• Testing and commissioning such as, e.g. status/controlling of variables or block status
functions.
• 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
cycle check point)
• PROFINET IO communication via PROFINET interface (system load)