Siemens SIMATIC ET 200AL, System Manual

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Functions
5.13 Accelerating startup
PROFINET with STEP 7
Function Manual, 05/2021, A5E03444486-AL
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Making the required changes to the user program
To accelerate the startup by making changes to the user program, follow these steps:
1.
Call the "D_ACT_DP" instruction to activate and deactivate the IO device at the start of the
OB 1 cycle.
If the IO device is replaced, the device that is no longer required must be deactivated and
the new device must be activated.
2. If you control the "Power ON" command of the IO devices via the application, then start the
activation of the IO devices via the corresponding call of the "D_ACT_DP" instruction as near
to the same time as possible. The IO device has to be physically connected for this.
3. You access the IO device using direct access commands after the "D_ACT_DP" instruction has
provided the feedback "IO device activated".