Rockwell Automation T8xxx Trusted Communications Interface - Manual (Page 29)

Trusted
TM
Communication Interface T8151B
Issue 21 Apr 10 PD-T8151B 29
Statistics Mode Control Variable Value Result
Max Scan Rate
False
→
True (Boolean)
0
→
non-zero (Integer)
Max value will remain until next cycle
completed.
Max value then updated with time of next
complete cycle.
True
→
False (Boolean)
non-zero
→
0 (Integer)
Triggers a reset
Scan Rate
False
→
True (Boolean)
0
→
non-zero (Integer)
No effect (data updated every cycle)
True
→
False (Boolean)
non-zero
→
0 (Integer)
No effect (data updated every cycle)
Average
False
→
True (Boolean)
0
→
non-zero (Integer)
Average value will remain until next cycle
completed.
Average value then updated with time of
next complete cycle.
True
→
False (Boolean)
non-zero
→
0 (Integer)
Triggers a reset
Table 8 Modbus Statistics Control
The master poll scan is defined as the time taken to poll all of the slaves defined for the master. The
first slave defined in the poll list is taken as the start and end point of the timing sequence. This is
illustrated in the diagram in Figure 10.
Sequence No. Message
1 Slave 1 Msg 1
2 Slave 2 Msg 1
3 Slave 3 Msg 1
4 Slave 1 Msg 2
5 Slave 2 Msg 2
6 Slave 3 Msg 2
7 Slave 1 Msg 3
8 Slave 2 Msg 1
9 Slave 3 Msg 3
10 Slave 1 Msg 4
11 Slave 2 Msg 2
12 Slave 3 Msg 1
13 Slave 1 Msg 1
14 Slave 2 Msg 1
15 Slave 3 Msg 2
Figure 10 Master Poll timing
Master
Poll 4
Master
Poll 2
Master
Poll 3
Master
Poll 1
Master
Poll 5