Explanation
In an S7 system:
The CPU is in the STOP mode because of a STOP command from the programming device or from a CFB (SFB 20 "STOP").

In an M7 system:
The event can also be indicated on a function module (FM).



Help on Event 5x71

Explanation

This event indicates the end of the start-up synchronization of the PROFIBUS DP master / PROFINET IO controller. If this event does not occur within the monitoring time you have set for the module ready message, the CPU forces the end of the PROFIBUS DP master / PROFINET IO controller start-up synchronization. The detailed information shows the number of stations that have indicated that they are ready.

S7-300:
The event is only generated if stations are missing at the end of the startup synchronization of the PROFIBUS DP master / PROFINET IO controller and a setpoint/actual difference is not permitted.

The number of existing stations is always registered as zero in the event.
看到上面，我没遇到这样的提示。。（背景：调试时候，有人刚好在远程末端的I/O站烧焊，结果末端的站点就烧了，CPU一个站都读取不了，重启也没有用）请教高手。。谢谢