Criteria for initial PA Allocation

In message <Pine.BSF.4.21.0105222115270.16621-100000 at atlas.rccn.net>, 
Carlos Friacas <cfriacas at fccn.pt> writes
>i remember someone once
>said... "640kb will be much more than we will ever need!" ;-)

It was, of course, a weak justification of an earlier address space 
exhaustion: splitting the 1MByte address space of a 16bit cpu into 16 
"slots" of 64K, 10 for RAM and 6 for ROM/Peripherals. With hindsight 
12/4 might have been a better choice - the moral being it was 
unfortunate that the split was inflexible.
-- 
Roland Perry