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Operation and Troubleshooting
Chapter 5
55
In the RUN mode, the interface can communicate with other nodes of the
Data Highway II link. When you power up the interface in RUN mode, it
goes through a reset cycle and a 15-second self-diagnostic test cycle
before seeking membership in a logical ring on the Data Highway II link.
Because each of the other switch positions causes the interface to reset,
the node seeks membership in a logical ring when you switch into RUN
mode.
In the momentary RESET mode, the interface goes through a reset cycle
and triggers a 15-second self-diagnostic test cycle that occurs when the
switch is returned to the RUN position. If this node is not in a logical ring
(because you pressed the EXIT REQUEST switch), resetting the interface
causes it to seek membership in the logical ring again.
After installing the 1779-KFM interface as we described in Chapter 4,
switch to TEST mode before you power up the interface for the first time.
This provides the most extensive test cycle to ensure that the interface is
operating properly before you attempt to communicate through it. Each
test cycle takes 50 seconds. If you leave the switch in the TEST position,
the interface will continuously execute the test cycle. Leave the switch in
the TEST position at least 15 seconds.
When you switch to the RUN position, the interface will continue through
the end of the current test cycle; if no faults are detected, the NODE PASS
indicator turns on green. At this point the interface is in the RUN mode.
In RUN mode:
Initially, the PORT READY indicator turns green and the
IN-RING/SEEKING-MEM indicator turns yellow to indicate that this
node is seeking membership.
If another node interface is connected in the Data Highway II link in
the RUN mode, the SIG QUAL indicator turns green and then the
IN-RING/SEEKING-MEM indicator turns from yellow to green to
indicate that this node is in a ring and receiving a token periodically.
If there is a cabling problem or no other node interface is in RUN
mode, every ten seconds the MAC board goes through a one-second
self-diagnostic test. This is indicated by the MAC TEST indicator
turning yellow and the IN-RING/SEEKING-MEM and REDUN
WARN indicators flashing rapidly.
If another node on the link has the same address, the DUP ADDR
indicator turns red.
Initially, the RS-422/449 port is not enabled, and the READY indicator
is OFF. When the RS-422/449 port is ready to transfer data, the
READY indicator turns on green. At that point, the port begins
Operating the 1779KFM
Interface