Rockwell Automation T8xxx Trusted Communications Interface - Manual (Page 37)

Trusted
TM
Communication Interface T8151B
Issue 21 Apr 10 PD-T8151B 37
The resultant message sequence on the communications link will be as shown in Table 14 below.
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
Table 14 Message Sequence
Where a slave has a minimum packet gap configured, each subsequent message for that slave will be
checked as in the sequence above. However, no message will be sent until the minimum separation
time between consecutive messages has been exceeded.
If a message in the slave sequence is disabled using an optional control variable, then at the
appropriate poll time the message will be skipped and the next enabled message for that slave will be
sent instead. If all the messages for a slave are disabled, then the slave will be pinged in the same
manner as if the slave had been commanded to standby mode.