Task/Response Ids - Siemens SIMADYN D Manual

Communications configuring
Mode of operation
3.22.1.6

Task/response IDs

Overview
3-260
• The PHS connections of block DPH and parameter blocks DPI1 and
DPI2 have the same name - "DEVICE". Thus, the parameter blocks
are assigned to the central block.
• Output QC of DPI1 is connected to input IC of DPI2. Further, output
QC of DPI2 is connected to input IC of the DPI1. Thus, the cascading
connections are connected with one another in a ring.
• Output QC of block DPI2 is initialized with 1. Thus, a negation is
injected into the cascading ring. Without this initialization, a parameter
block would never be able to issue a task.
• Both parameter blocks are enabled, i.e. the connections are 1.
• A task is created at both parameter blocks by specifying a constant
value. For block DPI1, it involves reading the value of parameter 30;
the DPI2 block issues a read task for the indexed parameter 96 with
index 1.
In the configuring above, the tasks, available at blocks DPI1 and DPI2
are cyclically processed. Thus, parameter 30 and indexed parameter 96
are cyclically read with index 1. The outputs of block DPI are not
processed in the example which, in a specific application would of course
be the case.
The mode of operation of the complete system is as follows:
• Output QC of DPI2 is initialized with 1.
• As output QC of the DPI2 is connected with input IC of block DPI1,
input IC has changed, as this is internally initialized with 0.
• DPI1 issues a task and waits for the response.
• If the device responds to the task, then DPI1 provides the response at
the outputs and negates its output QC. Thus, input IC of block DPI2
changes.
• Block DPI2 issues its task, waits for a response, which is output at the
outputs of the block, and in turn, negates its output QC.
• The DPI blocks, interconnected in a ring-type structure, are processed
once and then the cycle starts again.
If a block is disabled (input EN set to 0), then this does not restrict the
other DPI blocks in the ring, as the block transfers a change at input IC to
its output QC, without actually issuing a task.
System- and communication configuring D7-SYS - SIMADYN D
Edition 12.2003