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Re: GA144 article

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On Thursday, August 2, 2012 7:38:37 PM UTC-4, Paul Rubin wrote:
> rickman <gnuarm@gmail.com> writes:
> 
> > I saw how you got the 3.5 number, but what is it's purpose?  There are
> > four instructions in a word.  Why call it 3.5 instructions?  
> 
> There's only 4 instructions per word if you can actually use all 4
> slots.  The 4th slot is useless a lot of the time because there are only
> 3 bits in it, so only 8 of the 32 possible opcodes can go into it, so
> you end up having to put a no-op there.  The other slots are also often
> not usable for instructions or cause an extra fetch, because you need to
> bring in a literal.  4 instructions is the maximum, and it's achievable
> only some of the time, so the average is less than 4.  I picked 3.6 as a
> reasonable-looking estimate.  If you've got a better one, go ahead and
> post it.
> 
> > Why are you adding 3500 to the other numbers you posted?  I don't see
> > the meaning of this calculation.
> 
> 3500 for the port delay per your post, plus some unknown (guesstimated
> above) amount for instruction fetch, averaged out across instructions.
> You wrote:
> 
> > GA144 data book page 19...
> > TIOREG IO register read/write opcode time @+ @b @ !+ !b ! 3250 3500 4100 pS
> > The last three numbers are Min Typ and Max timings
> 
> 3500 according to you is typical, so I used that.  Again, if you don't
> like my estimate, feel free to post your own.  I don't think there is
> enough info to do a really reliable calculation, but the available info
> seems like a reasonable starting point.  Otherwise we have to assume the
> worst possible case, which is intolerable delays in getting stuff around
> between nodes.

I don't know what you are doing.  You are explaining the tiny details and not the overall picture.  

Rick

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Re: GA144 article Daniel Kalny <dkalny@seznam.cz> - 2012-07-24 02:37 -0700
  Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-24 03:12 -0700
    Re: GA144 article stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-24 10:36 +0000
      Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-24 10:28 -0700
        Re: GA144 article Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-24 22:12 +0000
    Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-24 14:49 -0700
      Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-26 13:25 -0700
        Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-27 13:17 -0700
          Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-27 14:31 -0700
            Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-27 22:02 -0700
              Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-28 23:03 -0700
                Re: GA144 article marko <marko@marko.marko> - 2012-07-30 09:12 +1000
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-31 01:09 -0700
                Re: GA144 article marko <marko@marko.marko> - 2012-08-01 00:19 +1000
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-31 09:59 -0700
                Re: GA144 article marko <marko@marko.marko> - 2012-08-01 10:13 +1000
                Re: GA144 article Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-01 00:59 +0200
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-31 16:54 -0700
                Re: GA144 article Luca Saiu <positron@gnu.org> - 2012-08-04 10:46 +0200
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-05 11:04 -0700
                Re: GA144 article Luca Saiu <positron@gnu.org> - 2012-08-06 02:02 +0200
                Re: GA144 article Mark Wills <markrobertwills@yahoo.co.uk> - 2012-08-06 02:16 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-30 08:23 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-30 21:33 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-31 01:51 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-31 11:48 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-07-31 14:54 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-07-31 16:09 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-01 12:57 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-01 14:16 -0700
                Re: GA144 article vandys@vsta.org - 2012-08-01 22:32 +0000
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-01 16:03 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-01 16:13 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-01 16:10 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-01 22:18 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-02 11:47 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-02 14:32 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-02 16:01 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-02 16:38 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-03 08:40 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-03 09:19 -0700
                Re: GA144 article rickman <gnuarm@gmail.com> - 2012-08-03 11:15 -0700
                Re: GA144 article Paul Rubin <no.email@nospam.invalid> - 2012-08-05 15:50 -0700
                Re: GA144 article Mark Wills <markrobertwills@yahoo.co.uk> - 2012-08-06 02:21 -0700

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