Block transfer data structure, Successful messages, Unsuccessful messages – Rockwell Automation 1336-GM1 Remote I/O Communications Module User Manual
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B–2
Supported Block Transfer Messages
Block Transfer Data Structure
Successful Messages
When an operation is successful, header word 1 of the drive response
contains a positive value (bit 15 = 0) and data follows.
Figure B.1
Example Message Structure and Reply
Unsuccessful Messages
When an operation is unsuccessful, header word 1 of the drive
response contains a negative value (bit 15 = 1).
If an error occurs, the drive also returns an error code to indicate the
reason for the failure. The location of the error code is typically data
word 3 in the drive response, but will depend on the message.
Figure B.2
Example Message Structure and Error Message Reply
The following table lists the error codes.
Decimal Value
PLC Request
Header Word 0
Header Word 1
Header Word 2
Message Length
Drive Response
Data
Data Word 3
Data
Decimal Value
Header Word 0
Header Word 1
Header Word 2
Message Length
Data
Data Word 3
Data
(OK)
Decimal Value
PLC Request
Header Word 0
Header Word 1
Header Word 2
Message Length
Drive Response
Data
Data Word 3
Data
Decimal Value
Header Word 0
Header Word 1
Header Word 2
Message Length
Data
Data Word 3
Error Code
(Error)
(See Table Below)
Value
Description
0
No error occurred.
1
The service failed due to an internal reason, and the drive could not perform the
request.
2
The requested service is not supported.
3
An invalid value in the block transfer request header word 2.
4
An invalid value in the block transfer request header word 3.
5
An invalid value in the block transfer request header word 2.
6
The data value is out of range.
7
There is a drive state conflict. The drive is in an incorrect state to perform the func-
tion. The drive cannot be running when you perform certain functions.