PORTIBM PC Portable (uses same BIOS as XT) 5C84 - EISA(Enhanced Industry-Standard Architecture) A 32-bit superset of the IBMInternational Busiuness Machines ATIBM PC AT's expansion bus (which is now known as the ISA or Industry-Standard Architecture bus). CONFIGURATION FLAGS (board in slot 5) 5C84 RW configuration flags (see #P1016)