PORTIBM PC Portable (uses same BIOS as XT) 1C80-1C83 - 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). board product ID (board in slot 1) 1C80 R? bit 7: unused (0) bits 6-2: manufacturer ID, first compressed ASCII char bits 1-0: manufacturer ID, second compressed ASCII char (high) 1C81 R? bits 7-5: manufacturer ID, second compressed ASCII char (low) bits 4-0: manufacturer ID, third compressed ASCII char 1C82 R? bits 7-4: first hex digit of product type bits 3-0: second hex digit of product type 1C83 R? bits 7-4: third hex digit of product type bits 3-0: product revision number (hex digit)