Rockwell Automation 1771-KA2 Communication Adapter Module - Manual (Page 104)

Start–up and Troubleshooting
Chapter 9
9-2
Figure 9.1
Module Indicator Combinations
Transmitting a
Message Receiving a
Message
Ready to
Send
Message Station Address
is 377
(Illegal)
Transmitting
Receiving
Ready
Program Status
Processor Link Status
On
On
On
On
Off
Off
Both
Flashing
Alternately
On
On
On or Off
Both
Flashing
Alternately
On
On
On
(momentary) On
(continuous)
On
Polling to
Relinquish
Mastership Communication
Zone of
Program
Being Checked Program
Fault in
Communication
Zone Processor
Communication
Fault Fault in Module
Memory Circuitry
Detected at
Power-up
12361
COMM
ADAPTER COMM
ADAPTER COMM
ADAPTER COMM
ADAPTER COMM
ADAPTER
COMM
ADAPTER COMM
ADAPTER COMM
ADAPTER
The following paragraphs describe each indicator and its significance to
the troubleshooter.
XMTG
The green transmitting indicator, labeled XMTG, turns ON when the
module is current master of the Data Highway. As described in chapter 8,
mastership means that the module is sending messages on the Data
Highway communication link. This may be a command, reply, or polling
message.
RCVG
The green receiving indicator, labeled RCVG, turns ON when the module
is receiving a message addressed to it. When both this indicator and the
XMTG indicator are ON, the module is polling.