Sign magnitude, one's complement, two's complement

Jay Jaeger cube1 at charter.net
Sat Aug 22 16:40:54 CDT 2015


Univac 1100 series - one's complement.

On 8/22/2015 4:23 PM, Sean Conner wrote:
> 
>   For my own morbid curiosity, and because it came up on another mailing
> list I'm on [1], what machines commercially avaialble were sign magnitude
> and one's complement?  Every machine I've encountered was two's complement
> (okay, IEEE 754 [2] is a sign magnitude format but I'm talking about integer
> implementations here, not floating point).  I've only found reference to one
> sign magnitude computer (the IBM 7090, release in 1959) and a few one's
> complement machines (mostly the PDP series from DEC).  
> 
>   Where there others?  And honestly, are there any machines that use
> anything other than two's complement today?  
> 
>   -spc
> 
> [1]	http://lua-users.org/lists/lua-l/2015-08/msg00386.html
> 
> [2]	AKA floating point.
> 
> 


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