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Parameter protocol, Parameter protocol -3, Figure 6.2 – Rockwell Automation 22-COMM-P PowerFlex Profibus Adapter User Manual

Page 57

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Using the Parameter Messaging

6-3

This protocol uses 4 words in the Profibus I/O area. Requests and
responses are a handshake procedure and cannot be batched, meaning
that if the master sends a request, it has to wait for the response before
sending a new request.

With this protocol you can:

• Read 8-bit or 16-bit parameters from any DSI port

• Write 8-bit or 16-bit parameters to any DSI port

• Read the Adapter Fault Code

• Read Events

• Read Diagnostic Items

Figure 6.2 Parameter Message Format

See

Parameter Message Request on page 6-4

and

Parameter Message

Response on page 6-5

for a description of the data that is required in

each word.

Parameter Protocol

Bit

15-12

11

10-0

15-12

11

10-0

Parameter Access

Word 1 (PCA)

RC

SPM

PNU

RC

SPM

PNU

Parameter Access

Word 2 (IND)

Subindex

Subindex

Parameter Access

Word 3 (PVA)

Spare

Spare

Parameter Access

Word 4 (PVA)

Parameter value

Parameter value

Request

Response