ProSoft Technology MVI69-DNPSNET - Manual (Page 78)

MVI69-DNPSNET ♦ CompactLogix or MicroLogix Platform Reference
Distributed Network Protocol Interface Module
Page 78 of 119 ProSoft Technology, Inc.
November 3, 2008
Cold Boot
This block is sent from the CompactLogix processor to the module (output
image) when the module is required to perform the cold boot (hardware reset)
operation. This block is sent to the module when a hardware problem is detected
by the ladder logic that requires a hardware reset. The structure of the control
block is shown in the following table.
Offset Description Length
0 9999 1
1 to n Spare n
Data Flow Between MVI69-DNPSNET Module and the CompactLogix or
MicroLogix Processor
The following topics describe the flow of data between the two pieces of
hardware (CompactLogix or MicroLogix processor and MVI69-DNPSNET
module) and other nodes on the DNP network. The DNP Server Driver allows the
MVI69-DNPSNET module to respond to data read and write commands issued
by a master on the DNP network. The following flow chart and associated table
describe the flow of data into and out of the module.
Step Description
1 The configuration information for the module is retrieved from the DNPSNET.CFG file on
the Compact Flash Disk. This information configures the module and define the Ethernet
node characteristics.
2 A Host device (DNP Master unit) issues a read or write command to the module's node
address. The driver qualifies the message before accepting it into the module.
3 After the module accepts the command, the data is immediately transferred to or from
the appropriate internal database in the module. If the command is a read command, the
data is read out of the database and a response message is built. If the command is a
write command, the data is written directly into the database and a response message is
built.