Siemens SIMATIC S7-1500T - Functional Principle of the Example Application

8 Example Application
8.3 Programming of the processing stations
TOs of S7-1500(T)
Entry ID: 109743134, V1.0, 05/2017
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Figure 8-4 Joint data management in the "ProductPositionTable” data block
Table 8-5 Configuration of the "ProductPositionTable” data block
Data element
Function
WriteIndex_MeasuringInput
Write index for the "PositionTable” array.
If the position value was entered in the table
through the measuring input unit, the index is
increased by one or set to the next index (ring
buffer function of "PositionTable”).
ReadIndex_SynchronousOperation
Read index for the "PositionTable” array.
The index shows the product that is currently
processed by the sealing unit.
ReadIndex_OutputCam
Read index for the "PositionTable” array.
The index shows the product that is currently
processed by the unit for the applying the
material.
MinIndex
Minimum index value as fixed value.
First entry of the "PositionTable” array.
MaxIndex
Maximum index value as fixed value.
Last entry of the "PositionTable” array.
PositionTable
"PositionTable” array in which the product
positions are entered in form of a ring buffer. This
means after "MaxIndex” the index restarts with
the "MinIndex” value.
8.3.2 Functional principle of the example application
The entire example application is now controlled via the indices in the joint data
management:
1. If a product is detected by the measuring input, the product position detected is
entered in the table and the write index of the measuring input is set to the next
index.
Thus, the product is available for the following production process.
2. If the read index of the sealing unit differs from the write index of the measuring
input unit, a product is available for processing. This starts the sealing unit.
If the sealing procedure is finished, the read index is set to the next index.
3. The same is the case with the read index of the unit for the material job. This
process is also started if there is a difference to the write index of the
measuring input unit.
If applying the material is finished, the read index is set to the next index.