8. Commands of the processing of the interruptions.
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   The Commands of the processing of the interruptions fill the field of 
microinstruction m/c BH1. The chip KM1804BH1 - is 8-digits microprogramming 
scheme (with ability to be increased) of the vector priority interruption, 
which produces processing by priority of inquiry for interruptions, which 
enter by eight buses from different devices.
   Commands of management m/c and types of their writing are brought Below:

    1)RESET - a command for cleaning;  
              can be without or with one operand;
              
           a)command RESET without operands conducts general clearing.
              While this command is executed the zeroizing of the register of 
              the condition occures and trigger of the permit of the request 
              of the interruption moves into condition, which allows leaving of
              the request of the interruption, a.w. system of the interruption 
              will react on the request of any priority

           b)RESET MR - a clearing the register of the mask(zeroizing all 
              digits of the register of the mask);  as a result 
              all interruptions will be unmasked.
              
           c)RESET IR   - clearing of the register of the interruption.

    2)CLR - a command of bitwise cleaning of  internal registers of the chip;  
            it is used to registers of the interruptions and masks:

           a)IR - can be realized by signals from data buse, register of the 
                   mask and register of the vector. For exemple:

              CLR IR ,00011000% ; \clean 4 and 5 digits 
              CLR IR , MR;   \clean that digits of the register of the 
                             \interruptions, for which the numeral in 
                             \ register of the mask corresponds
              CLR IR , VR ;  \occurs zeroizing those of IR , 
                             \which corresponds with the vector of the 
                             \interruptions,located in register of the vector

           b)MR   - realized by signals from data buses.

    3)SET - is a command of the bitwise installing of the register of the mask.
            For instance: 
              SET MR , 11100000%;\masking hte interruptions, 
                                 \which enter from 8,7 and 6 external devices;
                                 \the rest of digits of the register of the mask 
                                 \are not touched
                                 
    4)READ - a command of the reading of the  register m/c;  
             it is used to registers of the mask, of the condition and of the 
             vector:

           a)READ MR;

           b)READ SR;

           c)READ VR;

             While these commands are executing the signals, reflecting by 
             condition of register of the mask, conditions and vector, are 
             given on data bus.

    5)DI - a prohibition of the request of the interruptions(occurs zeroizing 
           of the trigger of the permiting of the request of the interruption).
           (command is without operands)
    6)EI - the permittion of the request of the interruption; the command acts 
           opposite command DI. (command is without operands)

   For all commands, where as second operand appears numerical value, shortcut
form is also equitable - without direct inputting of the data;  then the data 
will enter on data bus not from the memory of the microinstructions, but 
forming in process of the performing of the microinstruction on the kit of 
the microprocessor. For instance:

                  {OE_ALU;     \allow the issue of the result of the execution 
                               \of operation on data bus in ALU
                   XOR R1,R4;  \execute the operation in ALU 
                   CLR MR;  }  \clean those digits of the register of the mask 
                               \that correspond to digits R1 and 
                               \R4 of ALU and do not coincide

   All commands, which read or give on data bus some values, work from younger 
digits of the bus; for instance, the command

                   READ VR;

   will issue the value of 3-digital register of the vector on three younger 
digits of the data bus.