> Now I remember people saying that an OS/2 16:16 address is
 > capable of going up to 512 meg.  I don't know how that could
 > be the case, unless the formula was x << 13 | y, which is a
 > VERY strange number of bits to be shifting!!!


See if you can find a book on protected mode assembler.

In short, in protected mode the CPU forms addresses in a different manner -
the "segment" register is used as a selector which translates to
a 24-bit linear address via descriptor tables.  The real mode limitation is
1 meg.

david

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