ProSoft Technology MVI71-DNP - Manual (Page 25)

Installing and Configuring the Module MVI71-DNP ♦ PLC Platform
DNP 3.0 Master/Slave Communication Module
ProSoft Technology, Inc. Page 25 of 172
August 23, 2007
Word Variable Name Description
28 DNP Slave object
unknown error
(Application Layer
Error) This value counts the number of times a request for an
unsupported object is received by the slave device.
29 DNP Slave out of
range error (Application
Layer Error) This value counts the number of times a parameter in the
qualifier, range or data field is not valid or out of range.
30 DNP Slave message
overflow error
(Application Layer
Error) This value counts the number of times an application
response message from the slave is too long to transmit.
31 DNP Slave multi-frame
message from DNP
Master error
(Application Layer
Error) This value counts the number of times the slave receives a
multi-frame message from the master. The application
does not support multi-frame master messages.
32 Free MemoryLSB
33 Free MemoryMSB
Free memory in module
When the block transfer interface is used, the status data is placed in the
module's internal database. If this data area is transferred to the processor in the
read data area, it will be passed from the module to the processor in a normal
BTR block. The format of the data is exactly the same as shown above, but the
user determines its position. Refer to the Reference Chapter for a complete
listing of the data stored in this object.
2.1.2 User Data
When the side-connect interface is utilized, the read and write data is moved
between the module and the processor without any ladder logic. The size of the
data area and position of the data areas in the module's database is determined
by the parameters set in the configuration file.
When the block transfer interface is used, ladder logic is required to page the
data between the module and the processor. The size of the data area and
position of the data areas in the module's database is determined by the
parameters set in the configuration file.
Module data is paged up to 60 words at a time from the module to the processor.
The Ladder Logic task is responsible for placing the data received into the proper
position in the data files.