Rockwell Automation 1771-KA2 Communication Adapter Module - Manual (Page 105)

Start–up and Troubleshooting
Chapter 9
9-3
RDY
The green message ready indicator, labeled RDY, turns ON when the
module has messages that it is ready to transmit. With this indicator on,
the module is ready to assume mastership when it is polled.
PROG
The red program status indicator, labeled PROG, indicates the status of
module checks on the communication zone rungs of program. (These
rungs are described in chapter 5.)
A 1771-KA2 module checks the communication zone rungs of program at
power-up and whenever the mode select switch on the processor is turned
from PROG to TEST or RUN. It also checks these rungs after any
received privileged write command is executed or whenever the Data
Highway/Processor cable is reconnected between the module and its
station processor. During this initializing procedure, the PROG indicator
turns on. After the module has checked these communication zone rungs,
and if it has found no errors in programming format for these rungs, the
module turns the PROG indicator off. However, should any programming
error be detected in the communication zone of program this indicator
remains on and module activity on the Data Highway is disabled. In this
event, the ERROR CODE storage word can be checked for an indication
of the problem. (Refer to section titled “Start-up Procedures” for start-up
procedures.)
Should the PROG indicator fail to run on momentarily at power-up, or
when the mode select switch is turned from PROGRAM LOAD (PROG)
mode, the switch-selected station number may not match the station
number in the header rung of the communication zone of program.
PROC
The red processor link status indicator, labeled PROC, tells you the status
of the module’s communication with the station processor. This indicator
must be off for normal communication.
Should the PROC indicator go on, one of the following problems may
have occurred:
Disconnection of the Data Highway/Processor cable, which connects
the communication adapter module and the processor
Power OFF at the processor
Fault in processor operation
Incorrect processor link communication rate switch-selected on the
module (Refer to section titled “Write Option Switch Assembly.”)