🚀 go-pugleaf

>The major microprocessors (that I know of) available in the market
>deal with parity only at the bus interface.  Are there large systems
>(mainframes, supercomputers) that perform additional parity checks
>internally and under what conditions?

While working for a minicomputer company, I heard that the major
difference between minicomputers and microcomputers was that minis did
error detection (and occasionally correction) on major functional data
paths, not just the bus, and micros didn't.  I believe that many
minis have internal parity checks - in particular Gould PN and NPs.
See the appropriate technical manuals.

Academic ref:
    In the Proceedings of the 8th Symposium on Computer Arithmetic,
    1987, Robertson has a paper on extending parity to check for
    correct functioning of ALUs, etc. -- eg. parity(sum)=sum(parity).
    	Coincidentally, I am doing a literature survey of computer
    arithmetic under Robertson - I can ask him for further refs if
    you want.

--
Andy "Krazy" Glew,  Motorola MCD,    	    	    aglew@urbana.mcd.mot.com
1101 E. University, Urbana, IL 61801, USA.          {uunet!,}uiucuxc!udc!aglew
   
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