2 dnpdata object – ProSoft Technology MVI69-DNPSNET User Manual
Page 39
Ladder Logic
MVI69-DNPSNET ♦ CompactLogix or MicroLogix Platform
Distributed Network Protocol Interface Module
ProSoft Technology, Inc.
Page 39 of 119
November 3, 2008
Name Data
Type
Description
UDP_ST_Value
INT
UDP Socket State Value
Busywithmsg
INT
DNP Busy with Message State
App_Fragm INT
Application
fragment
Tx_frame_ST
INT
Transmit frame State
TCP_msg_len
INT
TCP message length
UDP_msg_len INT UDP
message
length
Port_Tx_St INT
Port
Transmit
state
Free_Mem DINT
Free
Memory
This information is important as it can be used to view the "health" of the module.
If the module is not communicating, examine the object to help find the problem.
Additionally, you should use the configuration/debug port on the module to
confirm that the desired configuration of the module is implemented.
DNPBackplane Object
The DNPBackplane Object stores the variables required for backplane data
transfer between the module and the processor. The structure of the object is
displayed in the following example:
Name Data
Type
Description
BlockTransferSize INT
LastRead
INT
Index of last read block
LastWrite
INT
Index of last write block
BlockIndex
INT
Computed block offset for data table
ReadData
INT[240]
Buffer File for data Read from Module
WriteData INT[240]
Buffer
File
for data Write from Module.
3.1.2 DNPData
Object
The DNPData object stores all the data for an MVI69-DNPSNET module.
Contained within the object is an array for each data type. The array sizes are set
to match the configuration set for the module. If multiple MVI69-DNPSNET
modules are used within a rack, a copy of this structure may have to be made to
permit each module to have its own database sizes. Ladder logic is required to
transfer the data in this structure between the module and the processor. The
structure of the object is shown in the following example:
Name Data
Type
Description
DNP_BI
INT[20]
Number of DNP BI data words
DNP_AI
INT[40]
Number of DNP AI data words
DNP_FLTI REAL[20]
Number
of DNP Float Input Points
DNP_Cntr DINT[10]
Number
of DNP counter double-words
DNP_BO
INT[40]
Number of DNP BO data words
DNP_AO
INT[40]
Number of DNP AO data words
DNP_FLTO REAL[20]
Number
of DNP Float Output points