MVI56-DNP
♦
ControlLogix Platform
Reference
DNP 3.0 Server
User Manual
ProSoft Technology, Inc.
Page 123 of 171
July 21, 2011
Read Command Error List Block (9950)
If the ControlLogix processor sends a block number of 9950 to the module, the
application will respond with a command error list. Each command in the system
has a data word set aside for its last error code. This value is set by the DNP
Master port command list task and the values correspond to the errors listed in
the error section of this documentation. This 300-word data area can be
accessed 200 commands at a time.
Word Offset in
Block
Data Field(s)
Description
0 Block
ID
This field contains the value of 9950 identifying the block
type to the module.
1
Number of
Commands to report
This field contains the number of commands to report in the
response message. The value has a range of 1 to 200.
2
Start Index of First
Command
This parameter sets the index in the command list where to
start. The first command in the list has a value of 0. The last
index in the list has a value of MaxCommands -1.
3 to 247
Spare
Not Used
The module responds to the request with a read block 9950 with the following
format:
Word Offset in
Block
Data Field(s)
Description
0 Reserved
Reserved(0)
1
Block ID
This is the next block requested by the module.
2
Number of
Commands reported
This field contains the number of commands contained in
the block that must be processed by the PLC. This field will
have a value of 1 to 200.
3
Start Index of First
Command
This field contains the index in the command list for the first
value in the file. This field will have a value of 0 to
MaxCommands-1.
4 to 203
Command List
Errors
Each word of this area contains the last error value
recorded for the command. The command index of the first
value (offset 4) is specified in word 3 of the block. The
number of valid command errors in the block is set in word
2 of the block. Refer to the command error list to interpret
the error codes reported.
204 to 248
Spare
Not Used
249 Block
ID This field contains the value of 9950 identifying the block
type to the PLC.
The ControlLogix program can sequentially step through the list of commands to
retrieve the value of the last error. To retrieve all 300 commands, this requires
two transfers.
