PORTIBM PC Portable (uses same BIOS as XT) 00A0 - XTIBM PC XT - NMIsee Non-Maskable Interrupt MASK REGISTER SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 0070h,INT 02 00A0 RW NMIsee Non-Maskable Interrupt mask register (XTIBM PC XT only) bit 7 = 0 NMIsee Non-Maskable Interrupt signal disabled from reaching CPU(Central Processing Unit) The microprocessor which executes programs on your computer. = 1 NMIsee Non-Maskable Interrupt signal enabled