Rockwell Automation 2708-DH5B2L_DH5B4L Attended Workstation - Manual (Page 69)

Chapter 6
Operating Procedures
6–6
Once the application programs have been loaded into the network
workstations, it may not be possible to see the status display, making it even
more difficult to recognize and solve network problems. When tracking
network problems, liberal use of the ENTER/OUT key combination to cause
brief display of the workstation status can be helpful.
The following is a collection of displays which may be helpful in identifying
(and solving) some network problems.
cc–nn WAIT
This workstation is waiting ONLINE to be polled.
When this appears on the display, the data memory of the workstation is full
and it is trying to send a transaction to the Host, but has not been polled. This
should only occur for very short periods of time (less than a second).
If waiting occurs for as long as a minute, the workstation will go into offline
operation.
If waiting occurs on a sporadic basis, then cabling may be the problem. Some
intermittent cable problems have been discovered to be the cause of sporadic
waiting. Verify that the Terminator has been set on either end of the string in
question; check individual cable connectioins to workstations and verify that
all workstations are operating.
If WAIT appears for more than a few seconds only during your peak usage
time, then too many workstations may be trying to send too much data to a
single Master. If this problem continues or worsens, consider laying out a
network with more than a single backbone (see chapter on Network Design).
nn READY
OFFLINE
The Master has stopped
polling this workstation
This indicates that the station is only able to store information in its local
memory, instead of sending data on to the Master. It will do so until either
the Master begins communicating again or the memory becomes full.
nn FULL
OFFLINE
The memory of this workstation
is full and offline
Network Problems (cont’d)
Workstation Status