 +_____________________________________________________________________
  AUTHOR:                                          SMS:  B20056     
    KEN KRESSIN          BFS PROGRAM NOTE          DR:   108659     
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  ORG/PHONE:          OPS NOTE (X)  USER NOTE ( )  DATE: 12/10/91   
   RID/(213)922-2146       RELEASE NOTE ( )                         
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  OI/FLIGHT EFFECTIVITY:          USER AFFECTED:                     
    OI-20, OI-21, OI-22           CREW (X)  GROUND (X)  DUMP ONLY ( )
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            MAJOR SOFTWARE AREA:             OPS MODES AFFECTED:     
 BSL( ) BSS(X) GNC( ) SEQ( ) SM/SP( ) IPL( )      0, 1, 3, 6         
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  SOFTWARE SUB-AREA: DISP                                             
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  PRINCIPAL FUNCTIONS: MG038101/3.1.1.5                               
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  TITLE:                                                              
   BFS DISPLAY TASKS SUBJECT TO IPV'S                                 
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  DESCRIPTION:                                                        
                                                                      
   REQUESTING A NEW DISPLAY WHILE CERTAIN TIMING CONDITIONS BETWEEN   
   THE MCDS INPUT MODULE (MIM) AND THE MCDS UPDATE MODULE (MUM) ARE   
   MET COULD CAUSE ONE OF THE FOLLOWING RECOVERABLE EFFECTS: 1) A     
   "BIG X" APPEARING ON THE BFS DEU'S, 2) GARBAGE APPEARING ON THE    
   NEW DISPLAY FOR UP TO ONE UPDATE CYCLE, OR 3) A "BLANK" DISPLAY    
   BEING SUPPORTED ON THE DEU WHICH RECEIVED THE NEW DISPLAY REQUEST  
   (ONLY THE MESSAGE LINE APPEARS AND UPDATES).                       
                                                                      
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  USER RESPONSE:                                                      
                                                                      
   IN MOST CASES, THIS PROBLEM WILL RESULT IN A "BIG-X" APPEARING ON  
   THE BFS DEU(S).  THE BFS DISPLAY(S) CAN BE REVIVED BY ENTERING A   
   "RESUME" KEY ON THE BFS DEU WHICH HAD THE MOST RECENT NEW DISPLAY  
   REQUEST.  IF THE DEU WHICH HAD THE MOST RECENT NEW DISPLAY REQUEST 
   IS NOT KNOWN, A "RESUME" KEY SHOULD BE ENTERED ON ALL BFS DEU'S    
   UNTIL THE DISPLAYS ARE REVIVED.  IN THE CASE OF A DEU SUPPORTING A 
   "BLANK" DISPLAY, A "RESUME" KEY SHOULD BE ENTERED ON THAT DEU.     
                                                                      
   NOTE: ANY NEW DISPLAY REQUEST, NOT JUST A "RESUME", WILL REVIVE THE
   DISPLAYS.  THIS INCLUDES "FAULT SUMM" OR "SYS SUMM" KEYSTROKES,    
   SPEC DISPLAY REQUESTS, DEU ASSIGNMENTS, MAJOR FUNCTION CHANGES TO A
   DEU, AND AUTOMATIC DISPLAY REQUESTS RESULTING FROM OPS TRANSITIONS.
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 CONCURRENCE:                           APPROVAL:                    
 RI: <S> J. AGRES          DATE 12/17/91                             
     --------------------      ---------                             
 FDSD:  W. R. PRUETT       DATE 01/09/92                             
      -------------------      --------- DARRELL E. STAMPER 01/10/92 
 PF MGR: D. STEPHENSON     DATE 01/09/92------------------- -------- 
        -----------------      --------- CHAIRMAN, SASCB      DATE   
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