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)