ProSoft Technology MVI69-101S - Manual (Page 96)

MVI69-101S ♦ CompactLogix or MicroLogix Platform Reference
IEC 60870-5-101 Slave Communication Module
Page 96 of 149 ProSoft Technology, Inc.
March 16, 2009
Balanced Mode
During balanced mode, the link must be initialized in both directions. The MVI69-
101S module also always reinitializes the link after it receives an initialization
request from the master. Therefore, the following initialization occurs during
balanced mode, after MVI69-101S boots.
After the initialization procedure is completed, the master and the MVI69-101S
start communicating. If during communication the master fails to respond to a
message from the module, the MVI69-101S will retry for a configured number of
times. If the master still fails to respond, the module will initialize the line again.
5.3.3 Monitor Direction and Control Direction
The protocol specification defines two directions of data: monitor direction and
control direction. These directions are defined by the protocol specification as
follows:
Monitor Direction: The direction of transmission from a slave to the master
Control Direction: The direction of transmission from the master to a slave