[comp.theory] Summary - 32 bit ops on 8 bit machine

ellis@motcid.UUCP (John T Ellis) (02/06/91)

A while back I posted a request for literature, insights, information on doing
32 bit operations on an 8 bit machine.  The responses were immediate and I
thank you.  Following is a list of people who responded and their summarized
tips.  I apologize for any errors in the list or tips.

Again, thanks for all the help.

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From: uunet!turing.cs.rpi.edu!borcherb (Brian Borchers)
From: uunet!stat.orst.edu!ross (David Ross)
From: uunet!jalapeno.cs.wisc.edu!bach (Eric Bach)
From: Piet van Oostrum <uunet!cs.ruu.nl!piet>
From: John Halleck <uunet!CC.UTAH.EDU!NAHAJ>
From: John Halleck <uunet!CC.UTAH.EDU!NAHAJ>
- Tim Iverson 
  iverson@xstor.com -/- uunet!xstor!iverson

   2nd volume Knuth's Art of Computer Programming (Seminumerical Algorithms)

Specifically, look at section 4.3, Multiple-Precision Arithmetic, and
sub-section 4.3.1, The Classical Algorithms.  He gives algorithms for doing
addition, subtraction, multiplication, and division on N-place numbers
(digits in an aritrary base; in your case, base 256) one "digit" at a time.

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Charles Rennolet
charles@thurse.MN.ORG

All you need to do is bit twiddle.

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From: L. Detweiler <uunet!longs.LANCE.ColoState.Edu!ld231782>

Generalize to base 255 and you have a byte based algorithm for division, 
multiplication, addition and subttraction.

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  John T. Ellis 708-632-7857   |  Always draw your curves, 
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