IBM RS/6000 SP, Maintenance Information

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MAP 0560: Block Multiplexer Channel Adapter Feature (BMCA)
015 (continued)
– Problem may exist with channel interface cables to host or attaching unit.
– Remove wrap plugs, P/N 8575337 (Bus) and P/N 8575338 (Tag) from end of the cable P/N
68F7211.
– Reconnect the channel-attach (mainframe) cables to the end of cable P/N 68F7211, which is far-
thest from the frame.
– Continue analysis from mainframe channel or call next level of support.
016
Problem was detected with the BMCA 78-pin cables or terminator connecting the BMCA cards.
– Isolate failing cable by moving terminator, swapping or deleting cables from string.
– Do not forget defective terminator or wrap plugs can cause failure.
– Refer to Figure 1-38 on page 1-355, while isolating fault.
Failing component isolated successfully?
Yes No
017
– Call next level of support.
018
– Replace defective component.
– Restore cables, wrap plugs, and terminator to original configuration.
– Rerun advanced diagnostics on the suspect BMCA (“cat0”) to verify repair.
Did the card and cable wrap diagnostics complete successfully?
Yes No
019
– Go to Step 016 to retest cables.
020
Problem resolved.
– Remove wrap plugs, P/N 8575337 (Bus) and P/N 8575338 (Tag) from end of the cable P/N 68F7211.
– Reconnect the channel-attach (mainframe) cables to the end of cable P/N 68F7211, which is farthest
from the frame.
– Inform the Customer that the channel resource is available.
– Go to “MAP 0570: End of Call” on page 1-357.
1-356
RS/6000 SP MAPs