你必须在OB100中调用SFB21 “RESUME”，原理及注意事项如下。

If there is a rising edge at control input REQ, SFB 21 "RESUME" activates a hot restart on the remote device selected with the ID.
The following conditions must be met if the remote device is a CPU:

1、The CPU must be in the STOP mode.

2、The key switch of the CPU must be set to "RUN" or "RUN-P."

3、When you created the configuration with STEP 7, you allowed for a manual hot restart.

4、There must be no condition preventing a hot restart.

Once the hot restart has been completed, the device changes to the RUN mode and sends a positive execution acknowledgement. When the positive acknowledgement is evaluated, the status parameter DONE is set to 1. Any errors that occurred are indicated in the status parameters ERROR and STATUS.

A restart can only be activated again in the same remote device after the previous hot restart has been completed.
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