Rockwell Automation 1747-ACNR15 ControlNet Adapter Module User Manual - Manual (Page 27)

Publication 1747-UM003A-EN-P
Planning to Use Your ControlNet Adapter Module 3-7
The ControlNet system places your scheduled transfers in the first part of each
Network Update Interval. Time is automatically reserved for network
maintenance. Unscheduled transfers are performed during the time remaining
in the interval.
Your application and your configuration-number of nodes, application
program, NUT (Network Update Time), amount of scheduled bandwidth
used, etc. determine how much time there is for unscheduled messaging.
Sch
ed
ule
d D
ata
T
rans
fer
s
Log
ic S
can
Data Update
H
ous
ek
ee
pi
ng
Data-
Table
Files
Private-
Memory
Buffers
Scheduled Data Transfer Program Scan
. . . . . .
You reserve a
specific amount
of time for all
scheduled
operations.
The system
reserves time for
network
maintenance
Any time remaining is used for
unscheduled operations
IMPORTANT
The ControlNet network reserves time for at least one
maximum-sized unscheduled transfer per update interval.
Depending on how much time there is for unscheduled
messaging, every node may not have a chance to send
unscheduled data every update interval.