strangest systems I've sent email from

Sean Conner spc at
Sat May 21 00:14:50 CDT 2016

It was thus said that the Great William Donzelli once stated:
> >   First off, can you supply a list of architectures that are NOT 2's
> > complement integer math that are still made and in active use today?  As far
> > as I can tell, there was only one signed-magnitude architecture ever
> > commercially available (and that in the early 60s) and only a few 1's
> > complement architectures from the 60s (possibly up to the early 70s) that
> > *might* still be in active use.
> There are probably a couple hundred Unisys 2200 systems left in the
> world (no one really knows the true number). Of course, when the C
> standards were being drawn up, there were many more, with a small but
> significant share of the mainframe market.

  Oh my!  I'm reading the manual for the C compiler for the Unisys 2200 [1]
system and it's dated 2013!  And yes, it does appear to be a 36-bit non-byte
addressable system.  


  I am finding chapter 14 ("Strategies for Writing Efficient Code") amusing
("don't use pointers!" "don't use loops!")  I suppose this is 1's complement
but I see nothing about that in the manual, nor do I see any system limits
(like INT_MAX, CHAR_MAX, etc).  

  -spc (Color me surprised!)


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