Technical data

Table Of Contents
Overview over the S7 Communication and the S7 Basic Communication
System Software for S7-300/400 System and Standard Functions - Volume 2/2
A5E00739858-01
20-11
Client Changes to STOP
If the CPU that initiated a job (and therefore established the connection) changes
to STOP during a data transfer, all the connections it established are terminated.
Making Program Changes
All parts of your program that immediately affect the calls for communication SFCs
for non-configured S7 connections must only be modified in the STOP mode. This
includes, in particular, deleting FCs, FBs, or OBs containing calls for
communication SFCs for non-configured S7 connections.
After modifying the program, you must perform a warm or cold restart.
Not following these rules can lead to resources remaining assigned and the
programmable controller being subsequently in an undefined state.