 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ]   S. ADAMS         ]    PASS PROGRAM NOTE        ]      105336      ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE:            ]
 ] IBM/713-282-7364   ]      RELEASE NOTE( )        ]     01/20/92     ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ]   OI-21 AND SUBS              ]  CREW ( )  GROUND (X)  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW ( )  GNC ( )  VU (X)  SM/PL ( )]     G9, PL9                     ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA:    SSME LOAD                                     ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS:  L5.2                                          ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ]          SSME LOAD MAY COMPLETE WITH CHANNEL FAIL INDICATION        ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ]    OCCASIONALLY, DURING THE SSME LOAD PROCESS, A CHANNEL 3 FAIL     ]
 ]    BIT WILL BE SET ON IN THE 60 KBIT DOWNLINK CONTROLLER DATA.      ]
 ]    THIS IS DUE TO (A) THE ENGINE INTERFACE UNIT (EIU) RECEIVING     ]
 ]    DATA TRANSMISSIONS (FROM THE GPC) SPACED LESS THAN 5 MSEC APART  ]
 ]    AND (B) THE EIU CHANNEL SWITCHING FROM MIA PORT 3 TO MIA PORT 4  ]
 ]    DUE TO BCE WHEEL ALIGNMENT SUCH THAT BCE 17 (EIU MIA PORT 4)     ]
 ]    EXECUTES BEFORE BCE'S 14 AND 15 (EIU MIA PORT 3 FOR EIU2 AND     ]
 ]    EIU MIA PORT 3 FOR EIU3).                                        ]
 ]                                                                     ]
 ]    NOTE:                                                            ]
 ]         1) PERFORMING THE SSME LOAD PROCESS IN REDUNDANT SET OPERA- ]
 ]    TIONS WILL INCREASE THE PROBABILITY OF THIS PROBLEM DUE TO THE   ]
 ]    EXIT SKEW OF THE INDIVIDUAL GPC'S CONTROLLING THE FLIGHT CRIT-   ]
 ]    ICAL BUSES.                                                      ]
 ]         2) EIU1 IS NOT AFFECTED IF LOAD IS PERFORMED IN A SIMPLEX   ]
 ]    CONFIGURATION.                                                   ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ]    THE USER SHOULD BE AWARE OF THIS ANOMALY AND EITHER VERIFY THE   ]
 ]    LOAD BY DUMPING THE CONTROLLER OR PERFORMING A RAM SUMCHECK.     ]
 ]                                                                     ]
 ]    THE USER SHOULD ALSO PERFORM A MULTI-PORT COMMAND TEST TO VERIFY ]
 ]    OPERATION OF MIA PORT 3,4 AND COMMAND CHANNEL 3 TO THE           ]
 ]    CONTROLLER.                                                      ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]IBM: PATTI A. THORNTON    DATE 02/25/92]                             ]
 ]    --------------------      ---------]                             ]
 ]FDSD:  ROBERT N. HINSON   DATE 02/28/92]                             ]
 ]     -------------------      ---------] DARRELL E. STAMPER 03/02/92 ]
 ]PF MGR: ERIC C. BINGHAM   DATE 02/25/92]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_______________________________________]_____________________________]
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