INT 02h (2)              Non-Maskable Interrupt (NMI)
 
    Generated whenever a non-maskable condition, such as a memory parity
    error, occurs.
 
    The default INT 2 handler displays PARITY ERROR 1 if there is a memory
    parity error on the system board, or it displays PARITY ERROR 2 if
    there is a memory parity error on the I/O channel memory. The handler
    will then attempt to find the location of the error. If the error is
    found, the segment address of the error is displayed; otherwise,
    '?????' is displayed. In either case, the machine then goes into an
    indefinite loop and is disabled until the power is turned off and back
    on.
 
    This is the only interrupt that cannot be masked out by the CLI
    instruction (Clear Interrupts).
 
       Notes:         The PC Convertible has the Non-Maskable Interrupt
                      attached to the diskette, real-time clock, keyboard,
                      and the system suspend interrupts.
 
                      The PCjr has the Non-Maskable Interrupt (NMI)
                      attached to the keyboard interrupt.
 
                      The math coprocessors generate this interrupt when
                      an error is encountered. The 8087 directly executes
                      this interrupt when an error occurs, whereas the
                      80287 and 80387--to maintain software compatibility
                      with the 8087--call the IRQ 13 interrupt handler,
                      which in turn calls INT 2.

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