Weidmuller WI-GTWY-9 User Manual page 111

WI-GTWY-9-xxx Wireless Gateway
DPV1 Acyclic Read
MSAC1_READ: Command Number = 0020h
This command initiates a DPV1 Class 1 acyclic read request. Consult EN50170 (DPV1) for more
information.
Command and response layout:
Message ID
Message Information
Command Number
Data Size
Extended Word 1
Extended Word 2
Extended Word 3
Extended Word 4
Extended Word 5
Extended Word 6
Extended Word 7
Extended Word 8
• Slave Address
Station address of the slave responder
• Slot Number &Slot Index
Used in the slave to address the desired data block.
• Length
This parameter specifies the number of bytes of the data block that has to be read. If the
server data block length is less than requested, the length of the response will be the actual
length of the data block. If the server data block is greater or equal, then the response will
contain the same amount of data.
The slave may answer with an error response if the data access is not allowed.
Command
(ID)
4002h
0020h
0000h
Slave Add Slot No.
Index Length
-
-
-
-
-
-
Response data byte 1
Response data byte 2
Response data byte n
Response
(ID)
0002h
0020h
(Size of data)
Slave Add Slot No.
Index Length
-
-
- Error Decode
Err Code1 Err Code2
Return Code
Fault Information
Data 1
Data 2
::: :::
Data n
V1.18
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