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Re: The difference between programmable and non-programmable logic--if

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Robert Myers <rbmyersusa@gmail.com> writes:


> If you take a *really* abstract view of digital devices, programmable
> or otherwise, they are devices that map the integers into the
> integers.

That basically takes you back to the Turing model of computing, where a
program takes all of its inputs when it starts and produces all of its
output when it ends.  Whether they are integers or tapes containing
symbols is of little consequence.

Modern computers interact, so you need a potentially infinite sequence
of inputs (events) and a potentially infinite sequence of outputs
(responses).  In addition of being potentially infinite, there is also a
possibility that future events may be influenced by past responses, so
you can't assume all inputs are available from the beginning: Some
inputs _are_ only available some time after certain outputs are
produced.

But you can see interactive computation as a function that maps a pair
of integers to a pair of integers and which is iterated in the following
way: One of the output integers (the state) is fed back as one of the
input integers and the other acts as input and output.  A zero input or
output could mean that no value is read or written, so you don't need to
have a strict interleaving of input-output-input-output ... .

Interrupts and so on can be modelled as inputs.  All that is required is
that there is a bound on the amount of computation between each i/o
step.

	Torben

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The difference between programmable and non-programmable logic--if there is one. Robert Myers <rbmyersusa@gmail.com> - 2011-10-22 19:14 -0400
  Re: The difference between programmable and non-programmable logic--if there is one. Del Cecchi <delcecchi@gmail.com> - 2011-10-22 20:52 -0500
    Re: The difference between programmable and non-programmable logic--if there is one. Andrew Reilly <areilly---@bigpond.net.au> - 2011-10-23 03:06 +0000
      Re: The difference between programmable and non-programmable logic--if there is one. nmm1@cam.ac.uk - 2011-10-23 09:50 +0100
    Re: The difference between programmable and non-programmable logic--if there is one. Quadibloc <jsavard@ecn.ab.ca> - 2011-10-23 09:22 -0700
  Re: The difference between programmable and non-programmable logic--if kenney@cix.compulink.co.uk - 2011-10-23 11:20 -0500
    Re: The difference between programmable and non-programmable logic--if Robert Myers <rbmyersusa@gmail.com> - 2011-10-23 18:23 -0400
      Re: The difference between programmable and non-programmable logic--if Del Cecchi <delcecchi@gmail.com> - 2011-10-23 19:46 -0500
        Re: The difference between programmable and non-programmable logic--if Robert Myers <rbmyersusa@gmail.com> - 2011-10-23 21:27 -0400
      Re: The difference between programmable and non-programmable logic--if torbenm@diku.dk (Torben Ægidius Mogensen) - 2011-10-24 10:36 +0200
        Re: The difference between programmable and non-programmable logic--if Robert Myers <rbmyersusa@gmail.com> - 2011-10-24 19:01 -0400
          Re: The difference between programmable and non-programmable logic--if Robert Myers <rbmyersusa@gmail.com> - 2011-10-24 22:56 -0400
            Re: The difference between programmable and non-programmable logic--if Terje Mathisen <"terje.mathisen at tmsw.no"> - 2011-10-25 09:18 +0200
          Re: The difference between programmable and non-programmable logic--if "Andy \"Krazy\" Glew" <andy@SPAM.comp-arch.net> - 2011-10-24 21:08 -0700
            Re: The difference between programmable and non-programmable logic--if Mark Thorson <nospam@sonic.net> - 2011-10-25 18:25 -0800
              Re: The difference between programmable and non-programmable logic--if BGB <cr88192@hotmail.com> - 2011-10-25 19:45 -0700
            Re: The difference between programmable and non-programmable logic--if Mark Thorson <nospam@sonic.net> - 2011-10-29 16:39 -0800
              Re: The difference between programmable and non-programmable logic--if BGB <cr88192@hotmail.com> - 2011-10-30 09:54 -0700
                Re: The difference between programmable and non-programmable logic--if Stefan Monnier <monnier@iro.umontreal.ca> - 2011-10-30 13:50 -0400
                Re: The difference between programmable and non-programmable logic--if BGB <cr88192@hotmail.com> - 2011-10-30 15:12 -0700
          Re: The difference between programmable and non-programmable logic--if Del Cecchi <delcecchi@gmail.com> - 2011-10-25 19:53 -0500
            Re: The difference between programmable and non-programmable logic--if Robert Myers <rbmyersusa@gmail.com> - 2011-10-25 21:29 -0400
              Re: The difference between programmable and non-programmable logic--if Quadibloc <jsavard@ecn.ab.ca> - 2011-10-26 08:57 -0700
                Re: The difference between programmable and non-programmable logic--if Robert Myers <rbmyersusa@gmail.com> - 2011-10-26 11:11 -0700
                Re: The difference between programmable and non-programmable logic--if Del Cecchi <delcecchi@gmail.com> - 2011-10-26 16:43 -0500
                Re: The difference between programmable and non-programmable logic--if jacko <jackokring@gmail.com> - 2011-10-26 14:45 -0700
            Re: The difference between programmable and non-programmable logic--if nmm1@cam.ac.uk - 2011-10-26 07:55 +0100
          Re: The difference between programmable and non-programmable logic--if MitchAlsup <MitchAlsup@aol.com> - 2011-10-26 18:03 -0700
            Re: The difference between programmable and non-programmable logic--if Stefan Monnier <monnier@iro.umontreal.ca> - 2011-10-26 21:43 -0400
  Re: The difference between programmable and non-programmable logic--if there is one. Terje Mathisen <"terje.mathisen at tmsw.no"> - 2011-10-23 23:28 +0200

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