PORT 0461-0462 - EISA NMI CONTROL

0461  RW  Extended NMI status/control register (see #P0890)
0462  -W  Software NMI register. writing to this register causes an NMI if
          NMIs are enabled
        bit 7 = 1  generates an NMI

Bitfields for EISA extended NMI status control register:
Bit(s)  Description     (Table P0890)
 7  R-  NMI pending from fail-safe (watchdog) timer
 6  R-  NMI pending from bus timeout NMI status
 5  R-  NMI pending from I/O port status
 4  R-  busmaster preemption timeout if bit 6 set
 3  RW  bus timeout NMI enable
 2  RW  fail-safe (watchdog) NMI enable
 1  RW  NMI I/O port enable
 0  RW  RSTDRV. bus reset
        =0  NORMAL bus reset operation
        =1  reset bus asserted

