MSW - Machine Status Word (286+ only)


      |31|30-5|4|3|2|1|0|  Machine Status Word
        |   |  | | | | +---- Protection Enable (PE)
        |   |  | | | +----- Math Present (MP)
        |   |  | | +------ Emulation (EM)
        |   |  | +------- Task Switched (TS)
        |   |  +-------- Extension Type (ET)
        |   +---------- Reserved
        +------------- Paging (PG)


        Bit 0   PE      Protection Enable, switches processor between
                        protected and real mode
        Bit 1   MP      Math Present, controls function of the WAIT
                        instruction
        Bit 2   EM      Emulation, indicates whether coprocessor functions
                        are to be emulated
        Bit 3   TS      Task Switched, set and interrogated by coprocessor
                        on task switches and when interpretting coprocessor
                        instructions
        Bit 4   ET      Extension Type, indicates type of coprocessor in
                        system
        Bits 5-30       Reserved
        bit 31  PG      Paging, indicates whether the processor uses page
                        tables to translate linear addresses to physical
                        addresses

        - see   SMSW  LMSW



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