User manual

905U-G Wireless Gateway User Manual
Page 105 ©September 2004
DPV1 Acyclic Write
MSAC1_WRITE: Command Number = 0021h
This command initiates a DPV1 Class 1 acyclic write request. Consult EN50170 (DPV1) for
more information.
Command and response layout:
Command Response
Message ID
(ID) (ID)
Message Information
4002h 0002h
Command Number
0021h 0021h
Data Size
(Size of data) (Size of data)
Extended Word 1
Slave Add Slot No. Slave Add Slot No.
Extended Word 2
Index Length Index Length
Extended Word 3
- -
Extended Word 4
- -
Extended Word 5
- - Error Decode
Extended Word 6
- Err Code1 Err Code2
Extended Word 7
- Return Code
Extended Word 8
- Fault Information
Message data byte 1
Data 1 Data 1
:::
::: :::
Message data byte n
Data n Data n
• 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 that has to be written. If the destination data
block size is less than requested, the response will contain an error message. If the data
block length is greater than or equal to the requested length, the response contains the
number of bytes that has been written. The slave may answer with an error response if the
data access is not allowed.
• Data [ 1 ...n ]
Data that should be written.
• Fault Information