 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ] K. BENIKE          ]    PASS PROGRAM NOTE        ]     34665        ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE:            ]
 ] VER/282-8451       ]      RELEASE NOTE( )        ] AUG. 1987        ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ] REL 18 AND SUBS               ]  CREW (X)  GROUND ( )  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW (X)  GNC ( )  VU ( )  SM/PL ( )] G1, G2, G3, G6, G8, G9          ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA: I/O, BUS                                         ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: SBIO                                           ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ] TRANSIENT I/O ERRORS WHEN DOWNMODING A RS TO OPS 0                  ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ] A TRANSIENT I/O ERROR CAN OCCUR ON A DEU, PL, LDB, OR FC BUS WHEN   ]
 ] A RS IS BEING DOWNMODED TO OPS 0. THIS IS BECAUSE THE FORMER RS     ]
 ] GPC'S MAY DIVERGE SLIGHTLY BETWEEN THE TIME WHEN THE GPC'S STOP     ]
 ] SYNCING TOGETHER ON RS I/O TRANSACTIONS AND THE TIME WHEN BUS       ]
 ] MASKS ARE SET BY EACH GPC FOR THE BUSES IT DOES NOT COMMAND.        ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ]  NONE.                                                              ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]IBM: WYATT COOPER         DATE 8/4/88  ]                             ]
 ]    --------------------      ---------]                             ]
 ]SSD: SAM ANKNEY           DATE 8/10/88 ]                             ]
 ]    --------------------      ---------] JACK BOYKIN         8/17/88 ]
 ]PF MGR: MICHAEL BRIEDEN   DATE 8/8/88  ]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_______________________________________]_____________________________]
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