Call Instruction In The User Program - Siemens SIMATIC S7-1200 Function Manual

3.5

Call instruction in the user program

The instruction of the software controller must be called in a cyclic interrupt OB. The
sampling time of the software controller is determined by the interval between the calls in the
cyclic interrupt OB.
Requirement
The cyclic interrupt OB is created and the cycle time of the cyclic interrupt OB is correctly
configured.
Procedure
Proceed as follows to call the instruction in the user program:
1. Open the CPU folder in the project tree.
2. Open the "Program blocks" folder.
3. Double-click the cyclic interrupt OB.
The block is opened in the work area.
4. Open the "Technology" group in the "Instructions" window and the "PID Control" folder.
The folder contains all instructions for software controllers that can be configured on the
CPU.
5. Select the instruction and drag it to your cyclic interrupt OB.
The "Call options" dialog box opens.
6. Select a technology object or type the name for a new technology object from the "Name"
list.
Result
If the technology object does not exist yet, it is added. The instruction is added in the cyclic
interrupt OB. The technology object is assigned to this call of the instruction.
PID control
Function Manual, 03/2017, A5E35300227-AC
Configuring a software controller
3.5 Call instruction in the user program
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