 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ]   PAUL M. TICE     ]    PASS PROGRAM NOTE        ]      107690      ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE (X)  USER NOTE ( ) ] DATE:            ]
 ]   LSIS/282-7297    ]      RELEASE NOTE( )        ]      07/27/94    ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ]   OI-22 THRU OI-24            ]  CREW (X)  GROUND (X)  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW (X)  GNC ( )  VU ( )  SM/PL ( )]   ALL                           ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA: SC, FCOS                                         ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: SDPS                                           ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ]         TECHNICAL VIOLATION OF BFS DISENGAGE REQUIREMENTS           ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ] IN THE RECOVERY OF A PASS GPC CONFIGURATION FOLLOWING A BFS ENGAGE, ]
 ] THERE IS THE POTENTIAL FOR PASS/BFS DUAL COMMANDERS ON ONE OF THE   ]
 ] FORWARD CRT BUSSES.  THIS CAN ONLY HAPPEN IF A SWITCH-RELATED       ]
 ] FAILURE OR A "SWITCH-TEASING" EFFECT OCCURS WHEN THE BFC DISENGAGE  ]
 ] SWITCH IS TOGGLED, SUCH THAT AT LEAST ONE (BUT NOT ALL) OF THE BFS  ]
 ] ENGAGE DISCRETES TRANSITIONS TO THE DISENGAGE STATE (0) WHICH IS    ]
 ] SEEN BY A MAJORITY OF THE PASS COMMON SET GPC CONFIGURATION.        ]
 ]                                                                     ]
 ] DK BUS DUAL COMMANDERS OCCUR BECAUSE THE PASS HAS RECOGNIZED THE    ]
 ] BFC DISENGAGE AND IS TAKING CONTROL OF THE SECOND FORWARD CRT       ]
 ] SPECIFIED BY THE BFC CRT SELECT SWITCHES, WHILE THE BFS IS STILL    ]
 ] ENGAGED (WITHOUT FLIGHT CRITICAL BUS CONTROL DUE TO ITS I/O         ]
 ] TERMINATE B DISCRETE BEING SET) AND IS STILL IN CONTROL OF THIS     ]
 ] SECOND FORWARD CRT.                                                 ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ] PRIOR TO TOGGLING THE BFC DISENGAGE SWITCH IN THE RECOVERY OF A SET ]
 ] OF PASS GPCS WITH BFS ENGAGED, HARD DEASSIGN THE SECOND FORWARD CRT ]
 ] SPECIFIED BY THE BFC CRT SELECT SWITCH POSITIONS VIA A PASS GPC/CRT ]
 ] KEYBOARD ENTRY.  THIS WILL PRECLUDE THE POSSIBILITY OF DK BUS DUAL  ]
 ] COMMANDERS WHEN THE BFC DISENGAGE SWITCH IS TOGGLED.                ]
 ]                                                                     ]
 ] A FIRM TOGGLING OF THE BFC DISENGAGE SWITCH WHICH IS REPEATED 2 OR  ]
 ] 3 TIMES IN A ONE SECOND INTERVAL WILL HELP ENSURE THAT ALL 3 ENGAGE ]
 ] DISCRETES TRANSITION TO THE DISENGAGE STATE.                        ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]LSIS: JEAN L. ZOPHY       DATE 08/23/94]                             ]
 ]     -------------------      ---------]                             ]
 ]FDSD: W. R. PRUETT        DATE 08/24/94]                             ]
 ]     -------------------      ---------] DARRELL E. STAMPER  08/25/94]
 ]PF MGR: KAYLENE KINDT     DATE 08/24/94]---------------------------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_______________________________________]_____________________________]
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