1+_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ] PAUL TICE          ]    PASS PROGRAM NOTE        ]     25159  *     ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE:  JULY 1987 ]
 ] IBM/282-7297       ]      RELEASE NOTE( )        ] REV B: 08/10/92  ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ] REL 19 AND SUBS               ]  CREW (X)  GROUND (X)  DUMP ONLY (X)]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW (X)  GNC ( )  VU ( )  SM/PL ( )] 0, G1, G2, G3, G8, G9,          ]
 ]                                   ]                                 ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA: FTS, OPS, TRANSITIONS, MMU                       ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: SDPS                                           ]
 ]_____________________________________________________________________]
 ] TITLE:   OVERLAY FAILURE FOLLOWING F-T-S DURING OVERLAY             ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:  * 15620, 33268                                        ]
 ] IF A  FAIL TO SYNC (FTS) OCCURS DURING GPC RECONFIGURATION, THE     ]
 ] FAILED GPC MAY CONTINUE THE TRANSITION ATTEMPT, AND THE OVERLAY MAY ]
 ] FAIL IN ONE OR MORE GPCS IN THE TARGET SET.                         ]
 ] DEPENDENT ON THE TIMING OF THE FTS DURING THE TRANSITION, THE FAIL- ]
 ] ED GPC AND ANOTHER GPC IN THE REMAINING RS MAY BOTH ATTEMPT TO COM- ]
 ] MAND THE OVERLAY ON THE SAME MMU BUS SIMULTANEOUSLY, I.E. DUAL COM- ]
 ] MANDERS.  OR, IF THE GPC SELECTED TO BE THE MMU COMMANDER FAILS     ]
 ] AFTER THE BUS SELECTION BUT BEFORE THE OVERLAY IS COMPLETED, THERE  ]
 ] MAY BE NO COMMANDER FOR THE MMU OVERLAY.  EITHER THE DUAL COMMANDER ]
 ] OR NO COMMANDER SITUATION CAN RESULT IN ONE OR MORE GPCS (IN THE    ]
 ] REMAINING TARGET RS) FAILING THE OVERLAY.                           ]
 ] A DUAL COMMANDER SITUATION MAY RESULT IN ONE OR MORE OF THE FOLLOW- ]
 ] ING I/O ERROR SIGNATURES LOGGED BY THE COMMANDER AND LISTENER(S):   ]
 ] INITIAL TIMEOUT, COMMAND SYNC, MIA BUSY, AND/OR MSC TIMEOUT ERRORS. ]
 ] A NO COMMANDER SITUATION WILL BE MANIFESTED BY INITIAL TIMEOUT      ]
 ] ERRORS LOGGED BY THE LISTENERS ON THE MMU BUS.                      ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ] IF THE FTS OCCURS DURING AN OVERLAY WHERE THE TARGET RS EQ THE CS,  ]
 ] THE FAILED GPC SHOULD BE POWERED OFF AND/OR MODED TO STBY/HALT AS   ]
 ] SOON  AS POSSIBLE TO ALLEVIATE THE POSSIBLE DUAL COMMANDER SITUA-   ]
 ] TION.                                                               ]
 ] HOWEVER, IF THE FTS OCCURS DURING AN OVERLAY WHERE THE TARGET RS    ]
 ] NOT EQ THE CS, THE FAILED GPC SHOULD NOT BE MODED TO STBY/HALT UNTIL]
 ] AFTER THE OVERLAY ATTEMPT IS COMPLETE (REF. USER NOTE 15620).       ]
 ] IN EITHER CASE, THE FAILED GPC SHOULD BE DUMPED AND RE-IPLED BEFORE ]
 ] ANY SUBSEQUENT USE.                                                 ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]IBM:    JEAN L. ZOPHY     DATE 09/15/92]                             ]
 ]    --------------------      ---------]                             ]
 ]FDSD:   W. R. PRUETT      DATE 09/21/92]                             ]
 ]     -------------------      ---------] S. N. HARDEE, JR.  10/07/92 ]
 ]PF MGR:   SCOTT SEYL      DATE 09/15/92]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_______________________________________]_____________________________]
 @
