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                       │ 1.CONSTANT FIELD. ║
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 Includes:
           D   - constant;
           OED - allow issue of the constant.


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 │ Field D ║  CONSTANT.
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 Purpose.
        1) Lowest  12  digits  are  used  to  shape  the addresses 
           transition  worked  out  from  MCU.  The  given  digits 
           constantly enter on bus  of the branching address if in  
           result of performing  the command in MCU (chip  BY4) is 
           formed a signal PE=0;
        2) All 16 digits can  be  used  to  assign the constants, 
           which  under  signal  OED=0  control  can be issued on
           system data bus.  This particularity allows:

           - first, reduce digits of ROM MI(the microinstructions)
           to account of the joining by flap;
           - secondly, enables to load the necessary  constants, 
           masks etc. in any device, connected to system data bus.

 The note. Values are entered in hex code.
           After entering the new command zero constant became assign.

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 │  OED   ║  ALLOW THE ISSUE OF THE CONSTANT ON ADDRESS BUS.
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 Purpose.
           The Permit of the issue all sixteen digits of the 
           field D on system data bus. Setting of given signal in 
           zero condition forms on system data bus condition of 
           constants of the field D.    .
 Level  :   0 - Active (the issue resolved); 
            1 - Passive (the issue prohibited).
 The note. 
           Values are entered in binary code(value 0 or 1).
           After entering the new command issue constants from 
           MIM on data bus is prohibited.
